Read above.
CREATIVE STEEL: CTS-V 8.8 Rear Diff Swap BOLT IN
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If the axles are sliding in at all then you have the same (31) axle/carrier spline count. If the CV is within an 1/8" from the axle seal in the housing then the axle is inserted all the way. If the axle doesn't seem to be "locking" in when installed, take a screw driver and "open up/stretch" that retaining ring just a tad, almost an unmeasurable amount. Open it too much will make installing the axle tougher and real tough to get the axle out someday down the road.
Call me if you still have questions, Max
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While I was here I thought I would bring you guys up to speed on a few things about the 8.8's.
One, if any of you guys that have our kits are having vibrations, check the clearance between the rear cover of the diff and the subframe, the location in question is where the modification we make to the covers comes closest to the subframe, just behind where the parking brake cable passes by. Not all of our cars are built the same, we modify all of the covers to the same height from the mating surface to the diff housing, I've got over a 1/4" of clearance on our car but some guys have reported clearance issues and now I've seen it first hand. We will be shortening the covers even more from now on, future 8.8 installers will never know this was ever an issue.
Two, if any of you are experiencing leaks with your 8.8, try switching to 75-140 gear lube. If not, then the 75-90 we send with the diff is still ok to use. People than spend prolonged periods on a track or the freeway that are having leaks are heating the 75-90 to the point that it is so thin that it is leaking past the seals. We have 75-90 in our car and its bone dry under there, but we spend almost no time on a freeway and the weather in Oregon rarely goes over 90 which probably helps the 75-90 not leak.
Three, we will be getting a prototype one piece carbon fiber drive shaft from the Drive Shaft Shop here real soon, I'm waiting on an email for a better time frame but two weeks or less is what I've been told.
I've got a few more things to pass along but need to go for now,
Peace, Max
Call me if you still have questions, Max
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While I was here I thought I would bring you guys up to speed on a few things about the 8.8's.
One, if any of you guys that have our kits are having vibrations, check the clearance between the rear cover of the diff and the subframe, the location in question is where the modification we make to the covers comes closest to the subframe, just behind where the parking brake cable passes by. Not all of our cars are built the same, we modify all of the covers to the same height from the mating surface to the diff housing, I've got over a 1/4" of clearance on our car but some guys have reported clearance issues and now I've seen it first hand. We will be shortening the covers even more from now on, future 8.8 installers will never know this was ever an issue.
Two, if any of you are experiencing leaks with your 8.8, try switching to 75-140 gear lube. If not, then the 75-90 we send with the diff is still ok to use. People than spend prolonged periods on a track or the freeway that are having leaks are heating the 75-90 to the point that it is so thin that it is leaking past the seals. We have 75-90 in our car and its bone dry under there, but we spend almost no time on a freeway and the weather in Oregon rarely goes over 90 which probably helps the 75-90 not leak.
Three, we will be getting a prototype one piece carbon fiber drive shaft from the Drive Shaft Shop here real soon, I'm waiting on an email for a better time frame but two weeks or less is what I've been told.
I've got a few more things to pass along but need to go for now,
Peace, Max
I want to commend Max and his team for finding out the source of the vibration on my V!!! Since GM has a wide range of tolerances on the production line, my car is one where the rear diff cover was too close to the subframe. This made a HUGE improvement and got rid of driveline vibration!
This 8.8 differential is an amazing upgrade on our V's!! As you go through turns, the rear is so well planted and you can drive MUCH close to the handling limits....as the rear steps out it is much more controlled and as you accelerate out of a turn the traction is amazing.
This 8.8 differential is an amazing upgrade on our V's!! As you go through turns, the rear is so well planted and you can drive MUCH close to the handling limits....as the rear steps out it is much more controlled and as you accelerate out of a turn the traction is amazing.
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Let me talk to DSS after I get the new carbon fiber unit, which should ship by the end of this week (5-10-13), after we put in the new one, maybe we could send the shaft that is in my car now to someone with vibrations to see if there is an improvement.
Addressing this question was one of the other things I wanted to pass along, but need to talk to Drive Shaft Shop before I make any promises. My fear is that ONE style/size of carrier bearing bracket will not solve the vibrations that some of the 8.8 cars are having. All of our cars are different in ways that we can't see, each responds to differently to new parts, including an 8.8 swap that does away with the rubber drive shaft coupler that is designed to absorb vibrations. My car and many others have the same carrier bearing support bracket with no vibrations at any speed.
Let me talk to DSS after I get the new carbon fiber unit, which should ship by the end of this week (5-10-13), after we put in the new one, maybe we could send the shaft that is in my car now to someone with vibrations to see if there is an improvement.
Max and others: When I had vibration, I really thought it was the carrier bearing bracket. Now, after clearancing the rear diff cover which was rubbing the subframe, all vibrations has disappeared!!! Just my .02 cents, but for those that have vibration issues, look at the front of rear differential cover where it comes close to the subframe.....shine a flashlight up there....if the rear diff cover is too close to the subframe it can cause a vibration sound which makes you think the entire drivetrain is vibrating.
UPDATE: The carbon fiber one piece drive shaft that I will be prototyping for our 8.8 kits has shipped from the Drive Shaft Shop, should be here the first of the week. Pretty exciting stuff.
Whats going on everyone? I thought I'd fill you guys in on the carbon fiber one piece drive shaft for our 8.8 kits. I received it from the Drive Shaft Shop about three weeks ago, got it installed the two weeks ago and have been driving it with no issues or vibrations. I've only tested it up to about 80mph, but according to DSS that should be fast enough for a "general purpose" test. I have 4.10 gears in my car so the drive shaft spins a bit faster than normal at any given speed and I have no vibes to report.
If you are interested in a CF drive shaft and you know you will be going faster than 80, remember that the CF drive shafts are made for each customer specifically; meaning at the time of purchase you will be asked what the top speed of your car will be along with gear ratio and tire size. This way DSS will have the "critical speed " of the shaft, then make the shaft that will suit your needs.
Here are a few pictures, one of the new shaft next to my old two piece, one after install and one of the CV that they use instead of the U-joint at the front end. I should also mention that the use of the CV at the front end of the shaft leaves a mile of room from the end of a short shifter to the bar that connects the CV to the carbon fiber section of the shaft.
Frank at the DSS also said that they can make a one piece shaft out of aluminum which will save a few bucks over CF, but also take the carrier bearing out of the equation which is a possible vibration cause.
I'll get our website updated on the prices. Thanks for being patient on this, I knew it would come.
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If you are interested in a CF drive shaft and you know you will be going faster than 80, remember that the CF drive shafts are made for each customer specifically; meaning at the time of purchase you will be asked what the top speed of your car will be along with gear ratio and tire size. This way DSS will have the "critical speed " of the shaft, then make the shaft that will suit your needs.
Here are a few pictures, one of the new shaft next to my old two piece, one after install and one of the CV that they use instead of the U-joint at the front end. I should also mention that the use of the CV at the front end of the shaft leaves a mile of room from the end of a short shifter to the bar that connects the CV to the carbon fiber section of the shaft.
Frank at the DSS also said that they can make a one piece shaft out of aluminum which will save a few bucks over CF, but also take the carrier bearing out of the equation which is a possible vibration cause.
I'll get our website updated on the prices. Thanks for being patient on this, I knew it would come.
I already have the DSS CF, just want too know if I will just need an adapter to hook it up to the 8.8, or do I have to ship the driveshaft back for modification?
Can you tell me how your current shaft connects to the rear diff? The OEM shaft has a CV joint and the DSS shafts use a U-joint or CV. I am of the mind that your current shaft would need to be sent back for modification, the 8.8 is longer from the center line of the axles to the pinion flange than the OEM Getrag diff is, this means the drive shaft for the 8.8 needs to be shorter than the one for the Getrag, which is especially problematic if we need room for an adapter.
Almost-7-year thread bump! 
I did the CS 8.8" install back in October '15, and have put about 40k miles on the setup. I've had some issues in that time, but nothing that I would attribute to CS's design. I used an aluminum housing, and the first shop that I gave it to to rebuild (with a new TrueTrac differential and Ford Racing 3.73 gears) did a piss-poor job it. As a result, after only a couple/few thousand miles it had to come back out (pinion bearing was already shot) and be rebuilt. I'm not sure the 2nd shop did a great job, either, as I've had gear whine pretty much from the start. (2nd rebuild used a fresh set of Ford 3.73 gears.) Also had a CV boot tear on one of the DSS conversion axles, and the experience dealing with DSS was a bit of a mess.
Anyway, I was bumping the thread just to share my recent experience. My car was down for most of 2019 with a cam issue that I took forever to fix. When I got the car back on the road and tuned, I quickly noticed I was getting a very pronounced clunk from the rear end if I wasn't very, very gentle with clutch pick-up. I've had the bushings on the snout of the 8.8" go bad once before, so I figured that's what it was.
Two weekends ago I put the car up on a lift and took a look. Turned out I was wrong - the bushings hadn't gone bad.
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Nope, the bushings hadn't gone bad - the passenger side ones had gone completely missing! Driver side still looked good, so that's nice.
Not surprisingly, I don't keep replacement 8.8" snout bushings in my glove box, so I had to come up with something. I was doing this at the auto hobby shop on base, and generally at the hobby shop there's a bin somewhere of spare nuts 'n' bolts. First big bolt I saw was the right thread pitch - huzzah! That still left me with no bushings, so I grabbed some big nuts and washers and just went solid for the time being.
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Fixed! :lol: I contacted Max & Kristie to order some replacement bushings and hardware. Kristie suggested I also do the differential block, so I ordered one of those, too, and CS modified it to fit my aluminum housing. [I had bought one a while back, but never got around to modifying it for the aluminum housing, so I ended up selling it to someone else.] Got the parts Thursday and went back to the auto hobby shop on base to fix things yesterday.
The temporary "solid bushing" fix had not lasted long at all - the bolt had already unthreaded itself. It couldn't fall out completely because of the exhaust nearly right below, so all the parts were still there:
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Took me a bit to get the differential block in there. I was fighting to try to slide it in from the passenger side, since the bushing was already gone on that side. After trying that unsuccessfully a few times, I figured out that if I removed the driver side mount bushing, then loosened the horizontal bolt that holds the adapter bracket in place, I could rotate the adapter bracket up and provide a bigger opening on the driver side to slide the diff block in from that side. Pretty easy once I had that revelation. Got the diff block in:
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[I also discovered that horizontal bolt was a little loose, enough that I could jiggle the forward adapter/mount bracket a bit. When I put things back together I made sure to gronk that down nice and tight.]
And then the new bushings in:
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The existing driver side bushing looked fine, so I re-used that, and kept the 2nd new bushing (and new bolt) as a spare.
Amazing what a difference fixing this made. The whole car seemed to ride smoother on the way home. I'll have to check the bolts again to make sure they don't loosen up like the temporary "solid bushing" fix did.
I did the CS 8.8" install back in October '15, and have put about 40k miles on the setup. I've had some issues in that time, but nothing that I would attribute to CS's design. I used an aluminum housing, and the first shop that I gave it to to rebuild (with a new TrueTrac differential and Ford Racing 3.73 gears) did a piss-poor job it. As a result, after only a couple/few thousand miles it had to come back out (pinion bearing was already shot) and be rebuilt. I'm not sure the 2nd shop did a great job, either, as I've had gear whine pretty much from the start. (2nd rebuild used a fresh set of Ford 3.73 gears.) Also had a CV boot tear on one of the DSS conversion axles, and the experience dealing with DSS was a bit of a mess.
Anyway, I was bumping the thread just to share my recent experience. My car was down for most of 2019 with a cam issue that I took forever to fix. When I got the car back on the road and tuned, I quickly noticed I was getting a very pronounced clunk from the rear end if I wasn't very, very gentle with clutch pick-up. I've had the bushings on the snout of the 8.8" go bad once before, so I figured that's what it was.
Two weekends ago I put the car up on a lift and took a look. Turned out I was wrong - the bushings hadn't gone bad.
Nope, the bushings hadn't gone bad - the passenger side ones had gone completely missing! Driver side still looked good, so that's nice.
Not surprisingly, I don't keep replacement 8.8" snout bushings in my glove box, so I had to come up with something. I was doing this at the auto hobby shop on base, and generally at the hobby shop there's a bin somewhere of spare nuts 'n' bolts. First big bolt I saw was the right thread pitch - huzzah! That still left me with no bushings, so I grabbed some big nuts and washers and just went solid for the time being.
Fixed! :lol: I contacted Max & Kristie to order some replacement bushings and hardware. Kristie suggested I also do the differential block, so I ordered one of those, too, and CS modified it to fit my aluminum housing. [I had bought one a while back, but never got around to modifying it for the aluminum housing, so I ended up selling it to someone else.] Got the parts Thursday and went back to the auto hobby shop on base to fix things yesterday.
The temporary "solid bushing" fix had not lasted long at all - the bolt had already unthreaded itself. It couldn't fall out completely because of the exhaust nearly right below, so all the parts were still there:
Took me a bit to get the differential block in there. I was fighting to try to slide it in from the passenger side, since the bushing was already gone on that side. After trying that unsuccessfully a few times, I figured out that if I removed the driver side mount bushing, then loosened the horizontal bolt that holds the adapter bracket in place, I could rotate the adapter bracket up and provide a bigger opening on the driver side to slide the diff block in from that side. Pretty easy once I had that revelation.
Got the diff block in:
[I also discovered that horizontal bolt was a little loose, enough that I could jiggle the forward adapter/mount bracket a bit. When I put things back together I made sure to gronk that down nice and tight.]
And then the new bushings in:
The existing driver side bushing looked fine, so I re-used that, and kept the 2nd new bushing (and new bolt) as a spare.
Amazing what a difference fixing this made. The whole car seemed to ride smoother on the way home. I'll have to check the bolts again to make sure they don't loosen up like the temporary "solid bushing" fix did.
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