: The final word on retrofitting the '09 differential



Cadillac Tony
02-16-08, 11:26 AM
There have been a lot of questions regrading the potential for retrofitting the improved 2009 CTS-V rear setup into our cars. I've spent the last few weeks researching the issue with a lot of help from some folks at GM (who shall remain nameless unless they say otherwise), and here's the final word- the following will be easier to understand if you have a working knowledge of the terminology of what's under your car:

Yes, it's possible.

No, it's not easy.

The biggest question (or so I thought) was whether the rear subframe cradle that everything attaches to would fit. It turns out that it will bolt right up, as the GMX322 chassis has the same cradle attachment points as our 320 chassis. This new cradle has all the correct provisions for holding the new rear diff in place, as it attaches to the cradle in a completely different way than our current one.

It turns out though, that this is the easy part. According the chassis engineers, our fuel tank will cause interference with the cradle, so we'd need to swap fuel tanks. Then the upper spring seats will not be in the correct location on our chassis, which means they would have to be moved. The unequal axle shafts from the 09 use a different spline configuration than our current ones, which means they won't mount to our 6 lug wheel hubs, so the hubs and rotors would also need to be changed to '09 pieces (as well as the wheels). There's also a new driveshaft in the 09 (Dana vs. GKN), so a new driveshaft is necesssary also.

So, to recap, it looks like you'd need the following:

-Rear cradle
-Fuel tank
-Differential
-Axles
-Hubs/rotors
-Wheels
-Driveshaft
-Modify upper spring seats

I suppose if one had a connection for cheap parts through GM, it could be done for about the same or less than the KARS cradle kit, and other than the spring seats, it would be a "bolt-on" modification (albeit a severe one). This would add not only the stronger rear diff, but cure the wheel hop as well, so I'm sure there's someone out there willing to try it next year when these parts become available to order.

Hopefully that answers the questions we've all had about doing this, and if there's anything I missed please feel free to shoot me a PM.

LUVMY04V
02-16-08, 11:37 AM
There have been a lot of questions regrading the potential for retrofitting the improved 2009 CTS-V rear setup into our cars. I've spent the last few weeks researching the issue with a lot of help from some folks at GM (who shall remain nameless unless they say otherwise), and here's the final word- the following will be easier to understand if you have a working knowledge of the terminology of what's under your car:

Yes, it's possible.

No, it's not easy.

The biggest question (or so I thought) was whether the rear subframe cradle that everything attaches to would fit. It turns out that it will bolt right up, as the GMX322 chassis has the same cradle attachment points as our 320 chassis. This new cradle has all the correct provisions for holding the new rear diff in place, as it attaches to the cradle in a completely different way than our current one.

It turns out though, that this is the easy part. According the chassis engineers, our fuel tank will cause interference with the cradle, so we'd need to swap fuel tanks. Then the upper spring seats will not be in the correct location on our chassis, which means they would have to be moved. The unequal axle shafts from the 09 use a different spline configuration than our current ones, which means they won't mount to our 6 lug wheel hubs, so the hubs and rotors would also need to be changed to '09 pieces (as well as the wheels). There's also a new driveshaft in the 09 (Dana vs. GKN), so a new driveshaft is necesssary also.

So, to recap, it looks like you'd need the following:

-Rear cradle
-Fuel tank
-Differential
-Axles
-Hubs/rotors
-Wheels
-Driveshaft
-Modify upper spring seats

I suppose if one had a connection for cheap parts through GM, it could be done for about the same or less than the KARS cradle kit, and other than the spring seats, it would be a "bolt-on" modification (albeit a severe one). This would add not only the stronger rear diff, but cure the wheel hop as well, so I'm sure there's someone out there willing to try it next year when these parts become available to order.

Hopefully that answers the questions we've all had about doing this, and if there's anything I missed please feel free to shoot me a PM.so about 10000 dollars worth of work :thepan: haha

Im in :)

Cadillac Tony
02-16-08, 11:38 AM
I'd say closer to half that if you do the wrench work yourself.

BowenCT
02-16-08, 12:10 PM
Wow, well done, Tony. Thanks for the due diligence. Who's gonna be the first?

rand49er
02-16-08, 12:34 PM
Yeah, like Bowen said, good work, Tony! :thumbsup:

A couple of ques:

Are the splines out of the tranny the same so the driveshaft change would be just a plug and play?

Seems to me the most difficult thing here is remounting the spring perch, or am I minimizing the gas tank swap, etc.?

At around $5k, this becomes doable. I'd sell both sets of wheels (stockers and the MMs) to help pay for it, and that would open up a whole bunch of cool options for new five luggers. Probably could sell other stuff, too, like my good diff. Hmm-m ... gettin' closer to $4k now and wouldn't have to worry about a couple of post-warranty diff hits to the wallet in the future.

Again, thanks for looking into this Tony! :worship:

LUVMY04V
02-16-08, 12:46 PM
Yeah, like Bowen said, good work, Tony! :thumbsup:

A couple of ques:

Are the splines out of the tranny the same so the driveshaft change would be just a plug and play?

Seems to me the most difficult thing here is remounting the spring perch, or am I minimizing the gas tank swap, etc.?

At around $5k, this becomes doable. I'd sell both sets of wheels (stockers and the MMs) to help pay for it, and that would open up a whole bunch of cool options for new five luggers. Probably could sell other stuff, too, like my good diff. Hmm-m ... gettin' closer to $4k now and wouldn't have to worry about a couple of post-warranty diff hits to the wallet in the future.

Again, thanks for looking into this Tony! :worship:

good point!! and yeah i forgot to say good work too tony :worship:

UnsafeAtAnySpd
02-16-08, 12:57 PM
Wow, this sounds really promising. Thanks for REALLY looking into this.

lawfive
02-16-08, 01:10 PM
Nice.

heavymetals
02-16-08, 01:15 PM
KUDOS.:thumbsup:

Cadillac Tony
02-16-08, 02:45 PM
Yeah, like Bowen said, good work, Tony! :thumbsup:

A couple of ques:

Are the splines out of the tranny the same so the driveshaft change would be just a plug and play?

Seems to me the most difficult thing here is remounting the spring perch, or am I minimizing the gas tank swap, etc.?

You're welcome, everyone- I started researching for my personal car, and wanted to share what I've learned.

Randy, I'll send an email inquiring about the driveshaft splines on the new piece and see if it will bolt up to our T-56. If not, I think a good driveline shop could adapt it (and for that matter, adapt your current driveshaft instead of buying a whole new one).

The gas tank is a cake walk once the rear cradle is out.

dieselp
02-16-08, 03:16 PM
Could the national highway traffic safety administration that is looking in to the diff failures force GM to recall and fit our cars with the new (safer) rear!!! It sounds like it would be a good fix for us and not crazy hard for gm. its better than gm getting sued for some one getting in an accident besause rear diff failure.

heavymetals
02-16-08, 03:37 PM
Don't hold your breath.

Don't expect GM to do anything and you probably won't be disappointed.

Our cars are obsolete.

Get used to it.

rand49er
02-16-08, 03:45 PM
... Randy, I'll send an email inquiring about the driveshaft splines on the new piece and see if it will bolt up to our T-56. If not, I think a good driveline shop could adapt it (and for that matter, adapt your current driveshaft instead of buying a whole new one).

The gas tank is a cake walk once the rear cradle is out.Tony, how hard/difficult would it be to alter the spring perch ... I can't recall what that looks like off hand ... are we talkin' a lot of cutting with a torch and then fitting and welding under there? ... UGH!

lunarx
02-16-08, 04:09 PM
Tony, how hard/difficult would it be to alter the spring perch ... I can't recall what that looks like off hand ... are we talkin' a lot of cutting with a torch and then fitting and welding under there? ... UGH!
Does having a Ground Control, (or other) coil-over spring perch make it easier to retrofit?

heavymetals
02-16-08, 04:24 PM
Hey Tony,

Can the 09 shocks be adapted (ie. bolt on?)

Gonna need a computer just to talk to um.:eek:

Never mind.....

Cadillac Tony
02-16-08, 04:28 PM
Does having a Ground Control, (or other) coil-over spring perch make it easier to retrofit?

I have no idea- I'm just passing along the answers to my questions as they were given to me. In the end, I'm sure there will be one or two things that no one saw coming that need to be addressed, and we won't know exactly what's involved until some pioneering soul gets hold of the parts and dives in headfirst.

The folks in several different areas of GM Powertrain and Chassis have been great for taking the time to research the information I asked for, especially at a time when they're focused on getting the new V ready for launch. I imagine that there's only so much info I can get out of these guys before someone tells me "Look- We just don't know, since we've never tried it."

Speaking strictly for myself, I'd rather spend $5k to get a bulletproof rear-end that will launch hard with no wheelhop than spend $5-$6k on mods. The gains in acceleration from this will probably make the car able to turn comparable times to a heavily modded V, but without all the tuning nightmares.

This thread was probably a year early, as it'll be at least that long before we can get our hands on any of these parts (when a new car launches, all the parts are NSA for a while for the purpose of keeping the factory rolling). I figured I'd share now so we can do a little brainstorming, and I'll keep firing questions their way until they tell me to get lost. :)

Cadillac Tony
02-16-08, 04:33 PM
Hey Tony,

Can the 09 shocks be adapted (ie. bolt on?)

Gonna need a computer just to talk to um.:eek:

Never mind.....

Errrrrr.....no. :lol:

heavymetals
02-16-08, 04:51 PM
For the hardcores sounds great.

Changes the rear to a five bolt so you can put some interesting size rims and tires.

And FACTORY PARTS :cloud9:

A year early?

Sounds like plenty of time to look at shocks, sways, and other things to make it work.

that will be one hell of a group buy! :histeric:

rand49er
02-16-08, 05:58 PM
... I'd rather spend $5k to get a bulletproof rear-end that will launch hard with no wheelhop than spend $5-$6k on mods. ...

... and I'll keep firing questions their way until they tell me to get lost. :)You're too late on the mod spending, but on the bright side, that's all I've got left to mod anyway! :D

And I for one certainly appreciate that you're bordering on becoming a pest for these guys/gals. If it helps at all, tell them that they owe us, but I'm sure you've already used that one. :sneaky:

Can't say it enough: THANKS, TONY!!!




... that will be one hell of a group buy! :histeric::highfive:

lunarx
02-16-08, 06:32 PM
Rand is right, that almost is the only mod we have left.
If we can have the improved drivetrain of the new V in our lighter chasis with similar or better WHP :cloud9:

I was already eying the 09V brakes and hubs, so I don't mind them bieng part of the plan.
I'm mostly glad to hear they will fit.

I'm thinking the spring perch relocation will just be a matter of an offset bracket with something similar to a Ground Control adjustable spring seat integrated into it.

StealthV
02-16-08, 06:51 PM
Within the first few weeks of introduction, there will be plenty of wrecked V2s to scavenge parts.

rand49er
02-16-08, 07:44 PM
Within the first few weeks of introduction, there will be plenty of wrecked V2s to scavenge parts.:histeric:

DILLIGAF
02-16-08, 08:24 PM
Maybe this could be adapted to fit in our cradle?Anything special about the size of the 5 lug pattern?

Venomous-V
02-16-08, 08:48 PM
Ok, we all agree that our diff problems start with wheel hop, correct? Has anyone noticed that in all the write ups for the new V, they state that they know the problems of the current V and to help "REDUCE" and "MINIMIZE" the whell hop in the new V they are using different diameter shafts! Does this not strike anyone as odd that no write ups say it has been completely resolved? Has me wondering how much hop will be in the new one.....Guess we will have to wait and see.

heavymetals
02-16-08, 09:43 PM
It won't go away in a independant rear suspension with that much torque.

The attributes contribute to the problem.

If you want to improve it to the point where it goes away, you will almost certainly have to use a straight axel and stiff suspension and no limited slip.

In other words a straight line car.

On the other hand, Kars said his system virtually eliminated the hop.

rand49er
02-17-08, 07:12 AM
Plus, others have mentioned that MANY IRS cars display wheel hop including Porches.

heavymetals
02-17-08, 03:40 PM
Plus, others have mentioned that MANY IRS cars display wheel hop including Porches.

Also, the more HP you add to the equation the more likely it's gonna happen.

Those magnetic shocks are looking good right now.........:suspense:

Let's see...

Pick up the G force from the computer and any other info, add an accelerometer, strain guages, and get some software and hardware together.

I would guess about $25k might cover it (less the shocks).

Those magnetic shocks ain't looking so good :thehand:

I need a beer...........:thumbsup:

ZEUSROTTY
02-17-08, 04:23 PM
wHY DO ALL OF THIS? Didnt you say the CTS-V doesnt have a diff problem? LOL... Just kidding!!! Doesnt seem like it would be that hard. Custom gas tank would be the tough part.



There have been a lot of questions regrading the potential for retrofitting the improved 2009 CTS-V rear setup into our cars. I've spent the last few weeks researching the issue with a lot of help from some folks at GM (who shall remain nameless unless they say otherwise), and here's the final word- the following will be easier to understand if you have a working knowledge of the terminology of what's under your car:

Yes, it's possible.

No, it's not easy.

The biggest question (or so I thought) was whether the rear subframe cradle that everything attaches to would fit. It turns out that it will bolt right up, as the GMX322 chassis has the same cradle attachment points as our 320 chassis. This new cradle has all the correct provisions for holding the new rear diff in place, as it attaches to the cradle in a completely different way than our current one.

It turns out though, that this is the easy part. According the chassis engineers, our fuel tank will cause interference with the cradle, so we'd need to swap fuel tanks. Then the upper spring seats will not be in the correct location on our chassis, which means they would have to be moved. The unequal axle shafts from the 09 use a different spline configuration than our current ones, which means they won't mount to our 6 lug wheel hubs, so the hubs and rotors would also need to be changed to '09 pieces (as well as the wheels). There's also a new driveshaft in the 09 (Dana vs. GKN), so a new driveshaft is necesssary also.

So, to recap, it looks like you'd need the following:

-Rear cradle
-Fuel tank
-Differential
-Axles
-Hubs/rotors
-Wheels
-Driveshaft
-Modify upper spring seats

I suppose if one had a connection for cheap parts through GM, it could be done for about the same or less than the KARS cradle kit, and other than the spring seats, it would be a "bolt-on" modification (albeit a severe one). This would add not only the stronger rear diff, but cure the wheel hop as well, so I'm sure there's someone out there willing to try it next year when these parts become available to order.

Hopefully that answers the questions we've all had about doing this, and if there's anything I missed please feel free to shoot me a PM.

V-Love
02-17-08, 08:01 PM
I am starting to like Tony!!! I GUARANTEE someone will do this. It won't be me but as our cars get older and out of warranty, it will happen. Awesome post Tony. :thumbsup:

StealthViggen
02-17-08, 11:15 PM
Why are we focusing on the V2 parts? Has the 2008 cts not been revised? i am sure there are plenty of those available wrecked now.

Flyboy
02-18-08, 05:15 AM
Why are we focusing on the V2 parts? Has the 2008 cts not been revised? i am sure there are plenty of those available wrecked now.

:wtf2:

CTSV_510
02-18-08, 10:43 AM
:wtf2:

he must be having a brain fart

StealthV
02-18-08, 11:16 AM
'09 V parts > '08 CTS parts

lunarx
02-18-08, 11:23 AM
Why are we focusing on the V2 parts? Has the 2008 cts not been revised? i am sure there are plenty of those available wrecked now.

This suggestion still has some merrit.
At least the cradle and gas tank could be the same.

CTS-2 diff would not be cast iron though.
Probably still stronger than V1 diff.

If the CTS-2 has stronger splines too, then that makes 2 good reasons for doing it.

The cast iron diff could always be put in later, if needed.

Obviously if you have big power then there is no option but to wait for the V2 parts.
With low mods, this might be a good low cost upgrade w/ cheap CTS-2 parts.

rand49er
02-18-08, 05:27 PM
Some enterprising Caddy dealership with a guy that specializes in selling mods to V owners should put a package together for retrofitting our cars with all the necessary components/mods to do this. Would be a real feather in his cap.

Any suggestions? :rolleyes:

ctsv154
02-18-08, 06:01 PM
Damn what was that guys name???.......................hmmmmmmmmm

Cadillac Tony
02-18-08, 06:07 PM
Quite frankly guys, my specialty is cars- both product knowledge and getting you a fair price on one. My sponsorship of the forum is personal, so my Parts and Service Department aren't involved. If anyone is going to put together a package for this retrofit it will be Luke and James, the fine fellows at Lindsay Cadillac.

My interest in finding this out is both personal and helping out fellow V owners, and if there's anyone qualified to take this info and run with it, it's those guys. :thumbsup:

rand49er
02-18-08, 07:57 PM
Well, out of the two guys I was thinking about, one has just nominated the other.

Tony, can't say it enough ... thank you, thank you, thank you for looking into the feasibility of doing this. :highfive:

lunarx
02-18-08, 08:21 PM
How about we have a raffle and the winner gets this upgrade done at Lindsay.
That will then pave the way for others to get their cars upgraded after. :)

ahahnu
02-18-08, 08:30 PM
Bitchin.

fred's maggie
02-18-08, 08:43 PM
I am a little behind in info what are the major differences 2005 vs. 2009 ?

heavymetals
02-18-08, 08:46 PM
Completely different cars.

CTSV_Rob
02-18-08, 08:59 PM
Good job Tony.

fred's maggie
02-18-08, 09:31 PM
Completely different cars.

sorry I should have stated I was asking about the rears :confused:

heavymetals
02-18-08, 09:52 PM
Completely different cars.

Read the Motor Trend write up.

rand49er
02-19-08, 04:52 AM
Where's Luke?

Should be punching in any time now.

trukk
02-19-08, 12:12 PM
Completely different cars.

:haha: HM is wise:wisdom:


Good job Tony.

:yeah:

-Chris

heavymetals
02-19-08, 01:42 PM
GREAT job Tony.

KUDOS.

Lindsay Cadillac Parts
02-19-08, 03:26 PM
Where's Luke?

Should be punching in any time now.


Im here (thanks heavy for telling me to read this thread) Im VERY interested in working with Tony on this one, we will see what happens

heavymetals
02-19-08, 03:30 PM
Hoo Ya! ;)

ahahnu
02-19-08, 06:00 PM
Why can't Lindsay franchise?

Cadillac Tony
02-21-08, 11:18 AM
To everyone who's said Thank You: You're welcome. :D

My reason for researching this is partly personal, and partly for the benefit of the community. Luke and I spoke yesterday, and will again today- we're working on figuring out the most cost effective way to get this mod to the market. Obviously, there's going to be a few unforeseen issues, and the parts won't be available for a while yet, but progress is being made on figuring out the easiest way to get this done. Lindsay will be the source for the parts, although I'm going to talk with my shop foreman about the possibility of helping people in the South who are too far away from Lindsay for it to be practical (as far as installation goes).

There will probably be some periods of inactivity in this thread while we wait for the SOP on the 09 V parts, so there's no need to keep bumping this up and cluttering the forum. If Luke or I have any updates, we'll post them here as we iron out some logistics. I'm looking forward to helping make it happen. :thumbsup:

heavymetals
02-21-08, 02:39 PM
"I'm looking forward to helping make it happen."

:worship: :worship:

CTSV_Rob
02-21-08, 02:43 PM
:worship:

rand49er
02-21-08, 03:03 PM
:woohoo:

Luna.
02-21-08, 04:43 PM
Lindsay will be the source for the parts, although I'm going to talk with my shop foreman about the possibility of helping people in the South who are too far away from Lindsay for it to be practical (as far as installation goes).

What about us slackers out here in CA? :D

LUVMY04V
02-21-08, 04:50 PM
:fwll::badger::nothing2add:

heavymetals
02-21-08, 05:21 PM
Hey Luna!

READ: BOLT ON :thepan:

:worship:

CTSV_Rob
02-21-08, 06:34 PM
I'm gonna to install this myself...

StealthV
02-21-08, 07:01 PM
http://www.billinexile.com/wp-content/uploads/south-park-kick-ass-2-3700244.jpg

CTSV_Rob
02-21-08, 07:40 PM
You gonna get yourself another Gen 1 now?

Cadillac Tony
03-08-08, 12:26 PM
Two (very) minor updates on this: I talked to Luke, and he had the idea to source custom axle shafts for the rear that would bolt up to our hubs, eliminating the need to replace the hubs, rotors and wheels. The cost shouldn't be more than ordering the 09 axles, but we'll need to wait until the parts show up in the computer before we know what the spline configuration, length and diameter are. Still looking for ways to make this as easy and inexpensive as possible.

On an unrelated note, I got another email from my contact at GM telling me that they just built two "Product and Process Evaluation" vehicles (one stick and one auto) that they'll be using to further test and evaluate the final build process. He's hopefully going to be able to drive them and share his opinion, but he already said that the idle sounds really mean. He also had this to say regarding the new diff:


I have sent an e-mail regarding the fluid spec. to the engineer tasked with development of the new cast iron rear diff. I failed to ask him while he was here at LGR, but he did say that they have tried to break this new unit and have thus far been spectacularly unsuccessful, so that is good news indeed. He was very bullish about the level of robust engineering that has gone into the part and sounds totally confident.

Things are looking good for a bulletproof rear. :)

CTSV_510
03-08-08, 12:38 PM
I think I speak for everyone when I say thank you Tony and Luke!

The Tony Show
03-08-08, 12:57 PM
Edited - nevermind.

StealthViggen
03-08-08, 03:29 PM
:wtf2:

I just mean that the 08 CTS diff and cradle has been updated already. Are we sure there is a substantial difference been the V and regular CTS? Not like There was not a difference on the first gen cars..

HiTechRV
03-08-08, 05:16 PM
Right. Basically couldn't you mock this up with parts from an 08 CTS (say a totaled car), then swap in the V parts when available?

StealthViggen
03-08-08, 06:01 PM
My thoughts exactly. Surely if the V2 has a better diff yet, then thats a swap, but the main problems here are the full bolt up of the cradle and associated components. The diff will just sit in there once that's sorted.

TrazzNJ
03-08-08, 09:02 PM
:yeah:

heavymetals
03-08-08, 09:27 PM
Hey guys, if your serious you should be talking to someone about a gas tank.

It has already been pointed out that it will need to go.

rand49er
03-09-08, 09:29 AM
Maybe didn't read this closely enough, but if this is primarily just a diff swap (from a drivetrain standpoint only i.e. excluding the fuel tank), is there any way to provide axle shafts with substantially different torsional rigidity in order to reduce/eliminate wheelhop?

I mean, if the biggest difference is simply going to be the diff, these cars are still gonna hop like a 'roo on 'roids.

lunarx
03-09-08, 10:33 AM
Maybe didn't read this closely enough, but if this is primarily just a diff swap (from a drivetrain standpoint only i.e. excluding the fuel tank), is there any way to provide axle shafts with substantially different torsional rigidity in order to reduce/eliminate wheelhop?

I mean, if the biggest difference is simply going to be the diff, these cars are still gonna hop like a 'roo on 'roids.

It's true that the car could still hop.

However, a full 09 retrofit (mayb even a 08 retrofit) with improved diff to cradle attachment and updated half shafts, should make it much better than it is now.

Cadillac Tony
03-10-08, 11:57 AM
When talking to GM I've been working on finding out the details on a complete rear replacement- diff, axles and cradle. The new cradle brackets for the diff take the bolts vertically instead of horizonatally, which should help quite a bit with deflection under load (along with stiffer bushings). The new axles are not only stronger, but also unequal in size and torsionsal stiffness which will help reduce the oscillation that makes it hop. Finally, the cast iron diff is there and able to take the punishment when you hook, or if the road conditions happen to cause a hop (which WILL still happen from time to time, even on the best cars).

The idea originally started with the hope that we could just bolt an '09 diff into our cradle- that would have made it last longer, but still not cured the hop. Turns out that won't work, but the bright side of the extra work needed is that it will also reduce the wheelhop by changing the necessary supporting pieces.

4DoorGTZ
05-18-08, 11:10 PM
Contemplating a quick fix for my newly imploded rear. Sourcing a used rear to let me drive the car this summer.

Hope to go ahead with the ''09 retrofit by...... fall/winter?

I'd be willing to drive cross continent for the work :) Can I camp out in the Lindsay parking lot, as long as there's wifi and power I'm good to go! (seriously tho, anyone thought of the logistics of getting this done far away from the east coast?)

lunarx
05-19-08, 02:43 AM
Contemplating a quick fix for my newly imploded rear. Sourcing a used rear to let me drive the car this summer.

Hope to go ahead with the ''09 retrofit by...... fall/winter?

I'd be willing to drive cross continent for the work :) Can I camp out in the Lindsay parking lot, as long as there's wifi and power I'm good to go! (seriously tho, anyone thought of the logistics of getting this done far away from the east coast?)
I'm already qualifying 2 potential shops to do the work, once the parts can be purchased.
This is one mod I can't wait for. :bouncy:

zxmarekxz
05-30-08, 07:52 AM
great job guys, now theres hope!!!

subscribed

heavymetals
05-30-08, 01:46 PM
Should be "subscribed and supporting member".

I look at the replacement gas tank as an opportunity to:

1. Hold more fuel.

2. Access and replacement of the fuel pump (something bigger or stronger for maggie guys)

Bang for the buck, this mod sounds like it will address the major complaint and with "factory parts".

Relatively cheap.

lonestranger
05-30-08, 03:22 PM
As the others had already said - You (and Luke) get a great big ATTABOY for attacking this issue so doggedly. (Just remember though, that one AW Shit, wipes out a thousand ATTABOYS!!:eek: Seriously, great job; of course you're not done yet, don't ya know!!:bouncy: I think Luke"s idea of custom axles is the way to go, as it obviously allows us to use the wheels, brakes and hubs we have (save money for more go-fast goodies) and would also allow possibly upgrading the u-joints on the half shafts even further.(just in case a LS-7 w/122 maggie showed up at the gun fight, don't ya know!!:rolleyes:

bpm
06-27-08, 11:50 AM
bump

Twitch
06-29-08, 06:27 PM
Anybody have a ballpark figure yet?

heavymetals
06-29-08, 07:11 PM
If you peruse back a few pages, I think it was hovering between $5k-6k but they are still working on the parts list.

I don't expect it to run much more then a maggie (installed).

What I expect to add up is changing the front hubs to a five bolt to match (if we end up having to) and if that is the case, rims and different tires.

The magnetic suspension would be a neat trick to (I wish). I bet that has a lot to do with the elimination of wheel hop. Just "lock it up" and ride the throttle.

StealthV
06-30-08, 03:34 PM
Seems the shocks are doable. They don't need to be integrated with the chassis controller for V1. Simply flip the "launch" mode toggle switch on the dash. Just need to figure out the trigger signal voltage. And that part is easy with a service manual.

The '09 update is the classic cost/value trade off. And yet another opportunity for GM Performance Parts to offer a factory blessed, DIY weekend bolt-on kit.

heavymetals
06-30-08, 04:02 PM
Yeah I look forward to them dropping the ball on this to. :yup:


Seems the shocks are doable. They don't need to be integrated with the chassis controller for V1. Simply flip the "launch" mode toggle switch on the dash. Just need to figure out the trigger signal voltage. And that part is easy with a service manual.

The '09 update is the classic cost/value trade off. And yet another opportunity for GM Performance Parts to offer a factory blessed, DIY weekend bolt-on kit.

lollygagger8
06-30-08, 04:20 PM
Bet those magnetic ones will be a pretty penny!

NormV
06-30-08, 09:00 PM
The C5 corvette(and C6 as they are using stronger C5 axles) uses the same number of splines as the V on the outer or hub side . This allowed me to bolt up C5 hubs on my V along with BMW wheels. The axle shaft diameter is identical between the C5 & V. Not sure about the number of splines into the diff.


Norm

StealthV
06-30-08, 10:13 PM
Just went and snapped a photo. If my count is right (where I my bifocals?) it's a 27-spline on the diff side.

Ja, ja, but what's the diameter?

The battery is dead in the calipers and I'm not digging out the old school version tonight (see bifocal note above). :D

http://www.cadillacforums.com/forums/attachment.php?attachmentid=43112&stc=1&d=1214878362

dvd_supercaddy
11-08-08, 10:33 PM
Any Updates? This is a huge and important thread

UnsafeAtAnySpd
12-15-08, 05:12 PM
Anything new on this?

Cadillac Tony
12-15-08, 06:01 PM
Luke and I spoke just the other day. I'm getting two CTS-Vs tomorrow (2009 models), at which time I'll be snooping around underneath them during the PDI process and comparing the length of the driveshaft and bolt pattern on the flange that bolts to the rear with a Gen.1 CTS to see if that's reusable.

As discussed earlier, the parts that will absolutely be necessary for this to be "bolt on" are the fuel tank, rear cradle, diff itself, new axles and a modification to the upper spring mounts for the rear. The driveshaft is still a question mark, and having custom axles made will definitely be the way to go (as opposed to replacing the hubs/rotors/wheels for the 09 parts).

I'll update here tomorrow.

smoothq
12-15-08, 06:11 PM
Luke and I spoke just the other day. I'm getting two CTS-Vs tomorrow (2009 models), at which time I'll be snooping around underneath them during the PDI process and comparing the length of the driveshaft and bolt pattern on the flange that bolts to the rear with a Gen.1 CTS to see if that's reusable.

As discussed earlier, the parts that will absolutely be necessary for this to be "bolt on" are the fuel tank, rear cradle, diff itself, new axles and a modification to the upper spring mounts for the rear. The driveshaft is still a question mark, and having custom axles made will definitely be the way to go (as opposed to replacing the hubs/rotors/wheels for the 09 parts).

I'll update here tomorrow.


You and Luke are Da man...

Naf
12-16-08, 12:57 AM
This woud be interestin...I know the new diff has more bolt points for better stability. Versus one that we have now...

It may be worth your while if you are out of warrantee and changin diffs quicker then you change clothes...

lollygagger8
12-16-08, 08:44 AM
Luke and I spoke just the other day. I'm getting two CTS-Vs tomorrow (2009 models), at which time I'll be snooping around underneath them during the PDI process and comparing the length of the driveshaft and bolt pattern on the flange that bolts to the rear with a Gen.1 CTS to see if that's reusable.

As discussed earlier, the parts that will absolutely be necessary for this to be "bolt on" are the fuel tank, rear cradle, diff itself, new axles and a modification to the upper spring mounts for the rear. The driveshaft is still a question mark, and having custom axles made will definitely be the way to go (as opposed to replacing the hubs/rotors/wheels for the 09 parts).

I'll update here tomorrow.

Man that's a lot of $hit to be changing.....but I hope it works!! Good luck mang!

lunarx
12-16-08, 10:33 AM
When looking at that 09 V, could you see if the front hubs, brakes & rotors are also interchangeable? :cool:

nmaier2201
12-16-08, 11:01 AM
My dealer is getting 3 in this week. All are "spoken for" already. I can always "stop by" with a camera and measuring tape if it will help out... I wish I could be more of a help, I feel helpless, worthless, and hopeful. I know there are a few forum members that took delvery of an 09 V we can pry tap them on the shoulder for some info if needed.

I would be also interested in hearing an update from Luke on the "sourced custom axle shafts" I think that's the key on making this easier and more affordable. It's exciting now that the V2 is becoming available.... I'll have to start watching the junkyards as totalled ones are soon to be showing up!

CTSV_Rob
12-16-08, 10:35 PM
When looking at that 09 V, could you see if the front hubs, brakes & rotors are also interchangeable? :cool:
IS she running yet??

I need to talk with you about a clutch, maybe one in my future soon.

smoothq
12-17-08, 10:49 AM
My dealer is getting 3 in this week. All are "spoken for" already. I can always "stop by" with a camera and measuring tape if it will help out... I wish I could be more of a help, I feel helpless, worthless, and hopeful. I know there are a few forum members that took delvery of an 09 V we can pry tap them on the shoulder for some info if needed.

I would be also interested in hearing an update from Luke on the "sourced custom axle shafts" I think that's the key on making this easier and more affordable. It's exciting now that the V2 is becoming available.... I'll have to start watching the junkyards as totalled ones are soon to be showing up!

Deffinatly wouldn't hurt to know measurments.

lonestranger
02-06-09, 08:51 PM
Tony;

Let me know if there is anything I can do to help with this VITAL project - as others have said,(to paraphrase) " really no point in other mods when the stock LS6 is already too much for the present diff package etc." I am in Bradenton, FL, retired, and my 05 V is just out of warranty! Time to fix it right!!:lildevil: Seriously, I have done a lot of "wrenchin" on all types of racecars and would welcome helping you and Luke with this project.

Best Wishes;
Lonestranger
(941) 932-5355 = cell #
traveler@raths.com

rand49er
02-06-09, 09:24 PM
Tony;

Let me know if there is anything I can do to help with this VITAL project - as others have said,(to paraphrase) " really no point in other mods when the stock LS6 is already too much for the present diff package etc." I am in Bradenton, FL, retired, and my 05 V is just out of warranty! Time to fix it right!!:lildevil: Seriously, I have done a lot of "wrenchin" on all types of racecars and would welcome helping you and Luke with this project.

Best Wishes;
Lonestranger
(941) 932-5355 = cell #
traveler@raths.com
WHOA! Here we go! Tony!

If you guys could get a firm handle on the specific steps needed to do this plus get a firm line on all the parts including part numbers, etc, ... enough to do an FAQ-worthy set of instructions, this would be very well-received. Seriously, though, it would be great to refine this conceptual remedy into a concrete set of steps and bill of materials to do this. Lonestranger is making a great offer with his assistance.

THIS PROJECT L-L-L-I-I-I-V-V-E-E-S-S !!!

Cadillac Tony
02-06-09, 09:43 PM
I'm going to be in the doghouse for saying this, but I just simply haven't had the time to go any further with the research. (ducks flying tomatoes) :duck:

As a former first Gen V owner and car nut, I definitely feel everyone's (differential) pain, but the shop has been overflowing with business lately and there's little tolerance for a nosy Salesman taking up two lifts to tinker with a V. There's also the slight issue of disassembling a brand new 2009 before selling it to someone so we can experiment- not gonna happen.

Lonestranger's offer is awesome, and it provides one of the pieces to the puzzle: A Gen 1 V. Unfortunately, there's several other pieces:

-Someone is going to have to be the person to order and pay for the parts, then deal with their car being down for an unknown amount of time while everything gets figured out. There will be speedbumps and unforseen parts needed- that you can count on with any project like this.

-Work will need to be done to the upper spring mount. How much, I don't know (and neither does my guy at GM). More parts may need to be bought or made at that point of the install

-The axles probably can't get made until someone has one of each (old and new), in hand to provide to the axle builder. I don't know if Luke ever nailed someone down to do that part.

-Ditto on the driveshaft. Now that this has been brought back to the front of my brain (thanks guys), I'll see on Monday if the Parts computer lists the dimensions for the driveshaft. I'd bet just about anything it's different.

Quite frankly, it's more of a job for a fabricator/speed shop than a Dealer. Most Service Managers won't let a Tech ignore customer/warranty work long enough to devote real time to this project, and if they did it would be at Dealer shop rates (:ohnoes:).

I'll continue to do what I can on my end to gather info. Since the Parts guys shoo me away when I hang out there too long, Luke can come through with the part numbers and prices (like always), but I suspect that the final project will be done either at a speed shop or by a Dealer mechanic after hours (which means the car will be down for a while).

Boy, that sounds awfully negative when I go back and read it. :lol: There's just still a lot of question marks that won't be answered until someone bites the bullet and says "I'm going to be a guinea pig, and it's going to cost some money and time".

heavymetals
02-06-09, 10:39 PM
Thanks Tony.

Well if I might suggest, a case for the 09 diff could be bought then someone could work on what it is gonna take to either get that bad boy to fit or if the whole carrier is gonna need to go.

I can see one hurdle is getting it (or for that matter any other diff) to fit without having to reroute the exhaust.

Also, I think it is going to end up being too expensive, but I hope I am wrong.

rjoffe
02-06-09, 11:20 PM
Well, I have one piece of the puzzle, I will donate one pair of V1 half shafts/axles (I have a spare set siting on the shelf) to the cause, as soon as someone is able to get a shop together, I will ship them the two axles.

There are plenty of drive shaft shops that can easily take two axles and cut and splice them for a first cut. I have priced this before and it should be in the $300 range.

Luke/Tony, does the computer provide a part number and a price for a VII Diff ?

Rey
02-07-09, 11:34 AM
Seems to me that a complete changeover to an '09 rear cradle assembly is not only very expensive, but also of little interest to CTS-V owners. The CTS-V production numbers are a fraction of Corvette, which in itself is consider quite small. Then, the numbers of those who seriously modify their CTS-Vs is much smaller yet. I suspect that all of them are active members of this forum. All this means is that it is unlikely any vendor is going to spend a lot of R&D money to produce and market this kind of modification.
What does seem more practical and doable is to adopt some of the changes made to the '09 cradle assembly - specifically the half shaft diameter changes. The differences in the '09 half shaft diameters is very important, I think. To really do the job right without a lot of engineering math, one would create two new half shafts using the same material and shaft diameters as the '09s. A less expensive change might be to just change a single half shaft on a V1, but this is more along the line of "Brute Force Engineering." Such a modification would be more reasonably priced, and much more marketable, provided it works.
At the end of the day, I do not think this mod wouild be a complete and total cure to the V1's wheel hop, but no doubt it will help somewhat.

rjoffe
02-07-09, 11:47 AM
Rey, That "less expensive change" has been discussed by many here (it's actually the reason I have a spare set of axles). However my concern is less about wheel hop (I can control that 100% with my right foot), and more about longevity of the diff. I know that my biggest concern with this car is what to do when the diff blows, I am out of warranty, and therefore will have to fork out $$$ for a new diff (V1 style). I don't believe a company will come out with a retrofit kit, rather a few of us will come up with the instructions to do it ourselves.

rand49er
02-07-09, 12:17 PM
Just like DoubleMint gum, you're both right.

Rey did hit upon one interesting point, and that is it would reasonably inexpensive do one halfshaft on a V1. Which one would be an issue (if it even really mattered), and the question wuld be how much would there be to gain ... a 2% reduction in WH (and associated improvement in the longevity of the diff) or would there be an 80% reduction. If it showed minimal improvement, then we'd know and focus elsewhere. If there was a dramatic improvement, then I'd think the market might be a couple dozen or maybe more (depending on price, of course). The experiment assessing the proposed "fix" would have to be controlled: same vehicle, same tires/pressures, same shocks, same pavement, same temps, same, same, same ... just different halfshaft.

heavymetals
02-07-09, 01:00 PM
As the prospect of any major mod like this is fast approaching over 20% of the value of the car (like a maggie), the market is shrinking.

I wish mods were tax deductible........:sneaky:

ctsv154
02-07-09, 04:34 PM
Instead of a whole cradle swap, just do the 09 axles, driveshaft or any one piece for that matter, and diff. If you can shove a Dana 60, 9" ford or 8.8" cobra diff in there than a V2 diff could be made to fit. Add the different size half shafts and you have helped to reduce the wheel hop and have a diff that can take the abuse if it did. Its already been said for a V2 cradle swap fabrication needs to be done so there will never be a bolt in solution. This way you dont need to buy the gas tank, rear cradle, and all that jazz. All you would need is the diff, a couple axles, and a drive shaft and a good fab shop. Everything you would need for the whole cradle swap but this leaves fewer parts to be purchased and maybe a tad bit more fabrication.

Here is another question. If you do swap tanks, will the existing sending unit be compatible with the new tank? Will we have to use the V2 sending unit and will it be compatible with the our car? Is the fuel filler in the same location? Are the straps in the same location? Are the fuel lines the same size? All this stuff would have to be figured out to do the V2 cradle swap. I say just modify the V1 cradle to accept the V2 diff and call it a day.

Albertan
02-07-09, 06:41 PM
Heavy
Actually, I CAN get a tax credit for doing research and development on my V! My company owns it and any money and time I spend developing anything with the possibility of future sales is fair game. I usually use this to try to develop new ways to do things in my molding business, but it would apply here as well.
As I see it, there are a number of different solutions. Number one in my mind is the offset front bushing location. Every time the car accelerates the whole housing will twist. Designing a second mount for the front would probably help a lot. Second, a girdle around the housing to prevent or minimize distortion due to gears pushing the case out of dimension. Both these fixes, designed correctly will probably make the dif live longer even with wheel hop. These are what I plan to work on since they should be minimal cost for max benefit.
So I will see if I can develop anything that actually will work and I can get an SR&ED tax credit while doing it. So a bit of win win!

heavymetals
02-07-09, 07:01 PM
If I had that kind of opportunity, I would be doing R&D on a V2. :thumbsup:

lonestranger
02-07-09, 07:19 PM
Just like DoubleMint gum, you're both right.

Rey did hit upon one interesting point, and that is it would reasonably inexpensive do one halfshaft on a V1. Which one would be an issue (if it even really mattered), and the question wuld be how much would there be to gain ... a 2% reduction in WH (and associated improvement in the longevity of the diff) or would there be an 80% reduction. If it showed minimal improvement, then we'd know and focus elsewhere. If there was a dramatic improvement, then I'd think the market might be a couple dozen or maybe more (depending on price, of course). The experiment assessing the proposed "fix" would have to be controlled: same vehicle, same tires/pressures, same shocks, same pavement, same temps, same, same, same ... just different halfshaft.

I agree that changing to 09 "spec" axles would be a step in the right direction, as to which axle to change, it would seem that should be in keeping with which one is the largest diameter on the 09 - specifically, endeavor to maintain the same ratio of differance between diameters as the 09 has. However, this axle would still not address the reported difference in splines between the 09 diff and the 04-07 V hubs, if the changes were "staged" at a different time. As to trying to adapt the 09 dif to the earlier subframe, I think there is a real advantage to using what the engineers have designed for 09(as well as being an OEM part) to mount and assure the diff is properly aligned and secured - that is the foundation on which the whole project should be based (remember, you may want to go 150+mph in this project,so peace of mind is also relatively important:lildevil:) - using as many OEM parts as possible is GOOD, (while also making the conversion relatively reversable, if ever it need be. As has been pointed out before, we are really looking at two problems that happen to be related/interrelated. The axles supposedly address WH, while the diff addresses longevity.That's my two cents worth!:D

That being said, being as how I have had a maggie in the box, along with other goodies, (kinky, no!:D) for almost two years waiting for a diff/launch solution (and my warranty to expire), so as I said, I am ready to move forward to try to solve the problem that keep our V's from being enjoyed the way they should be. Unfortunatley, my fab shop source of 30 yrs, passed away last year, so I would offer my 05 as a mule, and fund the parts (asking Luke to be gentle!!;)) if we can find someone in the group that has fabrication facilities/capabilities they could donate (or at least also be gentle:D), preferable in the Southeast/East.

ctsv154
02-07-09, 08:40 PM
The cradle does have its short falls but is not necessarily the whole problem. Its how its mounted to the car that is causing the biggest problems. Granted, I think it would be better to have a V2 cradle in the car and if it was a reasonable solution I would be all for it. I was just looking for a cheaper yet equally effective solution.

@ Albertan,

I suggested the second pinion brace when nutz started building his steel diff and of course it got shot to shit by him because he was trying to sell his idea and of course everybody was on his side. Now look at his all mighty diff. It may not break but nobody can afford it nor are they willing to spend that kind of cash on something that does nothing for the hop. Which may I remind everybody is what I said when he was building it and people yet again shit on what I said like I was trying to be a prick and bash his idea.

I still think that if you can get rid of some of the torsional stress on the case produced by the off set bushing that would do wonders for diff longevity. I still cant figure out why he spent so much building a diff yet never even looked at addressing the wheel hop that causes 99% of diff failures. Hmm I wonder if it was because he was trying to make a buck? Nutz also stated that wheel hop is all in the axles. Which its not. Yeah some of it may be due to equal torsional strength in the axles but 95% of the problem lies in how the cradle is designed and how it was attached to the car.

The cradle is not best design. With the trailing arms being mounted in front of the forward mounting points on the cradle, it really loads up the bushings in the cradle itself. Stiffen the mounting points and you can over come the short falls of the cradle design. This is why the kars kit works. It stiffens the front of the cradle and keeps it from wrapping up. The kars kit mounts to the trailing arm mount and is then attached to the body of the car. If the cradle mounts were in front of the trailing arm mounts, I dont believe we would be having this conversation as wheel hop would not be as prevalent and much more controllable.

This is the hot rod magazine solstice that originally sparked the idea for a pinion support for the V

http://www.hotrod.com/projectbuild/hdrp_0605_pontiac_solstice_project_v8_engine_build/photo_19.html

heavymetals
02-07-09, 09:15 PM
It is of little or no use to stroll down memory lane as to what was said or recommended in regards to NUTZ's endeavor (which is to be applauded) IMHO

The elimination of a lot of wheel hop can be achieved by getting rid of every rubber suspension part. Cradle bushings ect...

My "holy Grail" for this week is a cradle that will accommodate a Holden 12 bolt.

ctsv154
02-07-09, 09:43 PM
Okay my rants over. I promise.

heavymetals
02-07-09, 10:18 PM
The guy spent a lot of money. Woopdy freakin do! Its not that hard to take a piece of metal, measure all of its dimensions, and make the same thing only out of better material. It just takes a lot of money but no great skill to accomplish. It takes absolutely no engineering to do that. Engineer a fix for the wheel hop and then you have my applaud.

And your contribution to helping with this has been exactly what? :histeric:

ctsv154
02-07-09, 10:25 PM
My rants over but let me try and explain why our cars hop so bad. It is simple mechanical leverage. With the trailing arm mounts in front of the forward cradle mounts, the forward cradle mounts now become the fulcrum and the trailing arm is the leverage. It acts like a teeter-totter. You push on one end the other end move the opposite direction. When it get to its limit it loads up and springs forward. With the engine putting constant pressure on the trailing arms they push back causing it to oscillate. Once its starts it will only end when one end stops pushing back, ie you loose a lot of traction and the wheel isn't giving the proper resistance to sustain the hop, or you remove the pressure by lifting off the throttle.

Again, this is why the kars kit works. It doesn't completely get rid of the hop because there are simply to many variable like tires, surface of the road, etc. but it does help. The reason it helps is because you have effectively moved the forward cradle mounts father forward removing some of the leverage of the trailing arms. Granted there is a lot of force and the kars support still gives and the mounts are still engineered wrong so you will still see hop under the right circumstances. If you could get the mounts out farther were the trailing arms were pushing in the middle of the cradle instead of one end, the oscillation could not start because there would be no leverage. This is not to say that now the control arms them selves wont start to hop, but this is were good shocks with proper dampening and rebound finally come into affect.

heavymetals
02-07-09, 10:31 PM
Wheel hop has been explained.

http://www.cadillacfaq.com/faq/answers/wheelhopexplained.html

ctsv154
02-07-09, 10:49 PM
The cause for wheel hop can be many things as that article stated. My statement was not a general statement to all cars like the article. I was pointing out the main flaw in the design of the CTS-V cradle that causes 99% of the wheel hop and why it is so prone to wheel hop. It can be fixed and without spending thousands upon thousands of dollars. People say the shocks are the problem. People say the drive shaft is the problem. People say the diff mounting is the problem. People say all that is the problem. The main problem is the cradle and the way it mounts to the car. I have yet to see a person acknowledge this and until you do, you will have wheel hop that no shock, no diff, and no drive shaft will fix because none of that is currently the cause of the hop.

Wheel hop is not unique to the V as many if not all IRS cars experience wheel hop at some point in there life. However, the CAUSE for wheel hop in the V is unique because of the way the cradle is designed and mounted. There is no guessing what the problem is. I just laid it out in front of you.

heavymetals
02-07-09, 10:55 PM
Because some people here drive the car harder then you do, a "fix" for wheel hop and exploding rear ends is being researched.

Obviously this thread is of no use to you, so you should probably quit posting in it.

rand49er
02-08-09, 09:45 AM
Hey, ctsv154, any chance you can put those ideas of yours into a step-wise series of schematic drawings for an old brain like mine? In particular, can you make it such that even I (not having the cradle and the associated links committed to memory) can visualize the wind up of torque before the tires break loose and the torsional force/stress buildup around the various suspension components and their attachment points?

I really like that very concise article of heavy's ... well explained, IMHO. Taking that and applying it visually to the V would greatly assist us aging engineers comprehend things without the need to crawl back under the car. :cool:

atdeneve
02-08-09, 01:19 PM
Really, you don't need a schematic. If you get a quick look at a picture of the cradle assembly (there should be some floating around here somewhere), you'll see it right away.

The trailing arm's mounts/attachment points to the cradle are actually forward of the cradle's mounts/attachment points to the unibody/frame - you get a whole lotta leverage. It introduces a huge amount of instability to the cradle. Really pretty assinine. Ranks right up there with the single offset front cradle mount.

atdeneve
02-08-09, 03:38 PM
Heres ya go:
http://i266.photobucket.com/albums/ii254/10secTy/Rear%20diff/CIMG3792.jpg?t=1230836610

Albertan
02-08-09, 11:45 PM
All this talk of "trailing arms" better refer to the rear two mounts on the differential itself because the trailing arms that go to the shock locations by the wheels see no twisting moment at all. They do see a whole lot of compressive forces when the wheels start to move foreward and the car wants to stand still though. In a solid axle coil spring design the upper and lower trailing arms do have to stop the axle from twisting, but in our cars it is solely the job of the three rubber mounted attachment points on the differential.
The more I look at it the more I wonder. The rest of the rear seems to be really heavy duty and then there is the weak looking aluminum differential, what weren't they thinking.

rand49er
02-09-09, 06:05 AM
... The more I look at it the more I wonder. The rest of the rear seems to be really heavy duty and then there is the weak looking aluminum differential, what weren't they thinking.I bet the engineers were either trying to appease the bookkeepers, or the bookkeepers themselves spec'd the diff. :rolleyes:

nmaier2201
02-10-09, 11:46 AM
bump

nmaier2201
04-10-09, 01:50 PM
Heres ya go:
http://i266.photobucket.com/albums/ii254/10secTy/Rear%20diff/CIMG3792.jpg?t=1230836610

ROFL... that's the cradle I just bought.

nmaier2201
04-10-09, 01:53 PM
oooops I just managed to hyperlink myself into an old thread... and then I unwillingly just bumed it.... sorry admins....

tbjs should get a laugh out of this, I was just giving him a hard time for doing the same thing....

vetteboy2k
09-22-10, 12:45 PM
Has anyone done this swap or even attempted it?

whisler151
09-22-10, 12:55 PM
Has anyone done this swap or even attempted it?

No. It sounds like it would be a lot cheaper (and easier) to just go with the Gforce 9" rear. Unless you own a fab shop and feel like trying the swap.

http://www.cadillacforums.com/forums/2004-2007-cadillac-cts-v-performance/208533-gforce-engineering-irs-fab-9-cts-7.html

liqidvenom
09-23-10, 04:20 PM
it would be good to have someone attempt it so we can see what realistically is involved in this.

MauiV
09-23-10, 07:46 PM
Did anyone ever get a 8.8 Terminator Cobra rear in one of these? Some local guys put mine on a rack and said either the 8.8 or an M5 diff would be where they would start but I spent the money on a Maggie instead.

MIAdragon
09-23-10, 08:46 PM
Did anyone ever get a 8.8 Terminator Cobra rear in one of these? Some local guys put mine on a rack and said either the 8.8 or an M5 diff would be where they would start but I spent the money on a Maggie instead.


I has one. Its simply collecting dust currently, however I have a sneaking feeling that I may be able to get it under the car shortly.

vetteboy2k
09-30-10, 03:23 PM
Looking to go this route or a G-Force 9", I have up for sale my brand new DSS Race Axles (in classified section) (http://www.cadillacforums.com/cadillac-classifieds/Cadillac%20CTS-Vs%20For%20Sale/p7163-DSS%20Race%20Axles%20Brand%20New%20Free%20Shipping .html), a Gen 4 differential w/UUC front diff Poly bushing, BMR Anti-Wheelhop Kit, BMR Pinion Support, BMR toe rods, and BMR trailing arms for sale. All BMR parts in Black Hammertone finish Great condition. Diff has approx 4,000 miles since installed, quietest of my past 2 diffs.

May have some other parts for sale too, need to check the garage. Willing to offer a great deal on all parts.

liqidvenom
09-30-10, 04:15 PM
start up a thread if you decide to go the v2 rear end route. people would be willing to learn and help if possible.

vetteboy2k
09-30-10, 09:50 PM
Been looking into it, looks like the cost is pretty high.

RippyPartsDept
09-30-10, 10:10 PM
'final word' - eh?

vetteboy2k
09-30-10, 10:33 PM
You can help with the final word putting together a parts list with costs.

liqidvenom
09-30-10, 10:38 PM
You can help with the final word putting together a parts list with costs.

at least with a parts list you can try to get some prices from junk yards etc.

vetteboy2k
09-30-10, 11:00 PM
still will need custom axles for the new diff to our hubs or swap to the newer hubs but they have a different wheel speed sensors so don't know how that will work with our ABS systems. So Custom DSS axles are the next best bet.

RippyPartsDept
09-30-10, 11:58 PM
if you can get me a VIN of a car that has the parts you want and a list of said parts I'll gladly lend a hand

liqidvenom
10-01-10, 12:25 AM
i think the parts list is in this thread already, you just need a vin off of a v2

RippyPartsDept
10-01-10, 12:36 AM
do you know what post number?
alternatively i can post a parts illustration and you guys can pick out the pieces

i'm heading to sleep now so i'll check up on replies in the AM

liqidvenom
10-01-10, 12:54 AM
do you know what post number?
alternatively i can post a parts illustration and you guys can pick out the pieces

i'm heading to sleep now so i'll check up on replies in the AM

Rear cradle
-Fuel tank
-Differential

this is from post 1. also maybe the bolts needed to mount these things. these three things would be the biggest purchases if bought new.

vetteboy2k
10-01-10, 07:07 AM
Besides the cradle, what about upper and lower control arms, will ours bolt on? Trailing arms, toe rods, spindles, brake lines, hubs ect... lots of little things if ours transfer over it would save a lot of money needing only what was posted above.

Fuel tanks are different as they are 17.5 gallon compared to 18 gallon. Not sure if our fuel components will transfer over or if need all new fuel parts. Although the new 09+ uses a pulse width control module instead of a regulator which can make things tricky.

RippyPartsDept
10-01-10, 08:28 AM
so then why bother?
wouldn't it be more sane to trad your V in on a V2 than to go through all this trouble?

liqidvenom
10-01-10, 09:50 AM
Besides the cradle, what about upper and lower control arms, will ours bolt on? Trailing arms, toe rods, spindles, brake lines, hubs ect... lots of little things if ours transfer over it would save a lot of money needing only what was posted above.

Fuel tanks are different as they are 17.5 gallon compared to 18 gallon. Not sure if our fuel components will transfer over or if need all new fuel parts. Although the new 09+ uses a pulse width control module instead of a regulator which can make things tricky. those other parts while numerous would be something people would have to deal with as they do this the first time. I would immagine if it connects to the cradle then you might need it, or at least take a look at it.


so then why bother?
wouldn't it be more sane to trad your V in on a V2 than to go through all this trouble?

well its like with many things on this vehicle which should be simple but it completely more difficult then need be. also this swap would be alot more affordable once someone does it and calls out what is needed. then you could just as easily go on ebay or car-part.com and buy the rear subframe out of a car, hopefully at a good deal and do this swap yourself. I am a big fan of the v2, just not sure its for me though.

vetteboy2k
10-01-10, 11:47 AM
I am liking the new V-Coupe!