: The silence has ended...fugg'n diff!



Slithering_Joe
03-09-09, 09:08 AM
For a little while, I was enjoying a nice quiet luxury sports sedan until yesterday. After a long drive down the turnpike yesterday, I started to hear a familiar whine coming from the rear of the car. Not as bad as the previous diff (yet) but now with less than 3000 miles on the new replacement, the whine is back. I thought many of you were beating the hell out of their cars to cause a new diff to whine but I proved my theory wrong there. I have never caused the new rear to hop, never drag raced, never road raced, etc. I have only owned it during the late fall and winter so the car is rarely used and it has less than 29,000 miles total on it. This car is a blast to drive & looks incredible but I hate having this doubt stuck in my mind where I may need a tow truck so early into ownership.

Will this car make it to 100,000 miles?

rand49er
03-09-09, 09:14 AM
The car will make it to 250k, but maybe not the diff.

Did you change out the fluid?

CadiBlk
03-09-09, 09:36 AM
The car will make it to 250k, but maybe not the diff.

Did you change out the fluid?

Werd. My fluid gets changed with every oil change.

Twitch
03-09-09, 09:44 AM
30K miles on my original diff. I didn't have any noise till I installed the specter bushings. The whine wasn't too bad, but I like it quiet on a long trip, and you could hear it over 70.
I put amsiol in the diff, but it still whined for a while. After a few hundred miles, she was quiet again. I get a little noise between 45-65 mph, but not a peep at interstate speeds.

Tony

Slithering_Joe
03-09-09, 10:02 AM
I haven't changed the diff oil yet. Since reading here that the diff oil is 'grape scented' and it is still under warranty, I figured, if I changed the fluid to something other than the $1B oil GM puts in they will have something to stick it to me if the rear fails.

YoshiV
03-09-09, 10:19 AM
Royal Purple...barely a whine out of my 45K mile old original diff!

lollygagger8
03-09-09, 11:04 AM
I used GM crap fluid, it whined.....changed to RedLine fluid, was quiet for a long time, then I heard a little. I installed the UUC bushing, and now it's whining like CRAZY

NormV
03-09-09, 11:21 AM
Complain to your dealership, not here. Or switch to heavier RP.

Norm

Slithering_Joe
03-09-09, 11:26 AM
Complain to your dealership, not here. Or switch to heavier RP.

Norm
Thought I'd share.

ProdigalSON
03-09-09, 11:56 AM
So which fluid is better as preventative maintenence for the rear diff Redline or Amsiol? Which one is used on the Vette's as my repair guys told me they could try that.

Thanks in advance!

lollygagger8
03-09-09, 12:11 PM
Complain to your dealership, not here. Or switch to heavier RP.

Norm

I'm willing to try a heavier weight fluid other than the 75w90 now.....what do you suggest/use Norm? I'd rather use RedLine (or Amsoil) I'm not a fan of RP.

NormV
03-09-09, 12:35 PM
'Joe, just teasing.

Lolly, 75w1XX is better than w90 Royal Purple. If your whining while cold, the fluid will dampen it when warm. No effect on MPG. :)

Norm

Slithering_Joe
03-09-09, 01:10 PM
Mine begins to whine under load after it heats up a bit from a long ride.

lollygagger8
03-09-09, 01:24 PM
So 75w140 won't be too thick for all seasons?

Mine does the same thing as Joe's.....it's quiet until it warms up.

92nsx
03-09-09, 01:34 PM
Will this car make it to 100,000 miles?

I hope so, lol. Im at 99K right now ;)

Slithering_Joe
03-09-09, 01:47 PM
I hope so, lol. Im at 99K right now ;)
Hijack my own thread: any surprises along the way?

NormV
03-09-09, 01:48 PM
I had no problems below freezeing. The heavy stuff will have no effect until warmed up. Never needed the 90w stuff. :)


Norm

lollygagger8
03-09-09, 02:33 PM
So there will be no probs going to 75w140 for all seasons then? (just making sure)

92nsx
03-09-09, 03:08 PM
Hijack my own thread: any surprises along the way?

Hijacking your thread, sorry no attentions on doing that to your thread. You asked it as a question in the OP, last sentence, and saw it wasn’t answered yet so I provided proof that it will/should make it to 100k miles. Since my V is pretty much there. As for any surprises, nope nothing yet with my rear end, its still there, with original oil/fluid:D

thebigjimsho
03-09-09, 09:42 PM
For a little while, I was enjoying a nice quiet luxury sports sedan until yesterday. After a long drive down the turnpike yesterday, I started to hear a familiar whine coming from the rear of the car. Not as bad as the previous diff (yet) but now with less than 3000 miles on the new replacement, the whine is back. I thought many of you were beating the hell out of their cars to cause a new diff to whine but I proved my theory wrong there. I have never caused the new rear to hop, never drag raced, never road raced, etc. I have only owned it during the late fall and winter so the car is rarely used and it has less than 29,000 miles total on it. This car is a blast to drive & looks incredible but I hate having this doubt stuck in my mind where I may need a tow truck so early into ownership.

Will this car make it to 100,000 miles?My first diff grenaded on massive wheelhop. Diff #2 was noisier than #1 right off the bat. It was never really quiet but it gave me 33k otherwise trouble-free miles.

Lindsay didn't like how loud it was just before my warranty was up so they replaced it. Diff #3 is quieter and so far, so good. But a loud diff does not mean failure is imminent.

And I believe Cadillac Tony posted part #s for the diff's internal clutches that cause the whine. You only replace those and keep the casing. For a fraction of a whole piece...

Twitch
03-09-09, 10:04 PM
I gotta search for that thread. But I thought he said it fixed the chattering, not the whine.
Hmmm.....

thebigjimsho
03-09-09, 10:59 PM
hmm...

Slithering_Joe
03-09-09, 11:08 PM
Hijacking your thread, sorry no attentions on doing that to your thread. You asked it as a question in the OP, last sentence, and saw it wasn’t answered yet so I provided proof that it will/should make it to 100k miles. Since my V is pretty much there. As for any surprises, nope nothing yet with my rear end, its still there, with original oil/fluid:D
Nah, I meant that I was hijacking my own thread by asking you if you had any other surprises along the 99,000 miles. Good to hear you have had good luck.



My first diff grenaded on massive wheelhop. Diff #2 was noisier than #1 right off the bat. It was never really quiet but it gave me 33k otherwise trouble-free miles.

Lindsay didn't like how loud it was just before my warranty was up so they replaced it. Diff #3 is quieter and so far, so good. But a loud diff does not mean failure is imminent.

How many miles do you have on diff #3?


...And I believe Cadillac Tony posted part #s for the diff's internal clutches that cause the whine. You only replace those and keep the casing. For a fraction of a whole piece...
I don't think the clutches are capable of causing any whining. (Except by the owner/driver). I've installed clutches in other diffs before to end the one-legger burnout.

thebigjimsho
03-09-09, 11:14 PM
About 12k miles on #3...

c4ss
03-10-09, 10:28 AM
My new diff is way quieter than my last one and has been that way for approx 2 thousand miles (since I got it). I'm hoping it stays that way. About the fluid, since Lindsay did it, I'm assuming it's the "crap" GM fluid right?

thebigjimsho
03-10-09, 12:37 PM
I don't have any real problems with the GM fluid. It's if the dealer forgets the added modifier where you run into problems.

NormV
03-10-09, 01:20 PM
I could be wrong but I thought there was one weight between w90 and w140.

Norm


So there will be no probs going to 75w140 for all seasons then? (just making sure)

lollygagger8
03-10-09, 01:31 PM
I could be wrong but I thought there was one weight between w90 and w140.

Norm

I didn't see it on redline's site....what fluid do you use? Amsoil? Direct me Obi Wan, cuz I will change it t owhatever helps the whine. Thanks Boss

thebigjimsho
03-10-09, 01:36 PM
75w90 Redline. No modifier needed...

lollygagger8
03-10-09, 02:26 PM
75w90 Redline. No modifier needed...

I'm already running that exact brand/weight and I can hear the whine now (since UUC bushing install) ......I want to know if
1) the heavier stuff is ok to run, and
2) if it'll quiet the whine

Twitch
03-10-09, 03:25 PM
I could be wrong but I thought there was one weight between w90 and w140.

Norm
Not sure the exact number, but Amsoil has one between w110 and w120. That's what I used. I was too chicken to jump up to w140, but this worked well for me.

Slithering_Joe
03-10-09, 03:33 PM
According to Amsoil, their Severe Gear 75W-90 meets GM specification 9986115. Something to consider if one is still under warranty.

thebigjimsho
03-10-09, 03:45 PM
If your diff whines, it whines. Unless you're not adding enough oil or are without modifier, I doubt the oil does much squelching...

lollygagger8
03-10-09, 03:52 PM
Nice word squelching tbjs! :2thumbs:

I use Redline 75w90 (has modifier in it) and fill it up til its coming back out the fill hole....come on man I'm not that dumb.

If the next weight will help with whine, I'm game for trying it. I will change my diff fluid 2x/yr anyways.

thebigjimsho
03-10-09, 03:53 PM
Nice word squelching tbjs! :2thumbs:

I use Redline 75w90 (has modifier in it) and fill it up til its coming back out the fill hole....come on man I'm not that dumb.

If the next weight will help with whine, I'm game for trying it. I will change my diff fluid 2x/yr anyways.
10-4 good buddy

NormV
03-10-09, 05:03 PM
RP. .

1) yes
2) yes

Norm


I'm already running that exact brand/weight and I can hear the whine now (since UUC bushing install) ......I want to know if
1) the heavier stuff is ok to run, and
2) if it'll quiet the whine

thebigjimsho
03-10-09, 06:16 PM
naww

thebigjimsho
03-10-09, 06:16 PM
ss...

CTSV_510
03-10-09, 07:43 PM
If you get a new diff you should change out the fluid after the 1500 miles or so (right?). I changed the GM fluid to Amsoil 75w-90 after 1000 miles.

I got a new diff in mid-August last year and have put 3500 miles on it since then. I haven't heard a peep out of this one, and I have not exactly been kind to it.


hmm...

thebigjimsho
03-10-09, 07:50 PM
so cruel...

ccextra1976
03-10-09, 08:06 PM
Nice word squelching tbjs! :2thumbs:

I use Redline 75w90 (has modifier in it) and fill it up til its coming back out the fill hole....come on man I'm not that dumb.

If the next weight will help with whine, I'm game for trying it. I will change my diff fluid 2x/yr anyways.

so is 1000 miles the recommended time? I have an new diff with 500 miles on it..Iwas going to change to Amsoil before Vday ....so I will have about 1500 miles on it at the time I change it??

thebigjimsho
03-10-09, 08:44 PM
I'd give it 1500. Still pissed I couldn't teach an S-type R and M5 a lesson during break-in...

ccextra1976
03-10-09, 08:52 PM
I'd give it 1500. Still pissed I couldn't teach an S-type R and M5 a lesson during break-in...

I feel your pain...I had to let a carrera s walk on me the day after I got it...I did hit once though:eek: couldn't let a blazer SS have his day in the sun (at the track that is:thumbsup:)

lollygagger8
03-11-09, 03:51 PM
RP. .

1) yes
2) yes

Norm

Thank you Sir

Twitch
03-11-09, 03:59 PM
Thank you Sir
If you go with the heavy stuff, let me know how it is after a few hundred miles.

lollygagger8
03-11-09, 04:08 PM
If you go with the heavy stuff, let me know how it is after a few hundred miles.

I thought guinea pigs were used for quieting down B&M shifters :lol:

I'll let ya know when it gets warm/nice enough to drive the dang thing after I change it out.

thebigjimsho
03-11-09, 06:14 PM
much ado about nothing...

darkman
03-11-09, 06:44 PM
According to Amsoil, their Severe Gear 75W-90 meets GM specification 9986115. Something to consider if one is still under warranty.

Amsoil Severe Gear 75W-90 does not, in fact, meet GM specification 9986115 although Amsoil's website implies that. We have this discussion before-see the thread below:

http://www.cadillacforums.com/forums/cadillac-cts-v-series-forum-2004/112552-proper-gear-oil-rear.html

Slithering_Joe
03-11-09, 10:44 PM
The seem to have re-worded by it mentioning: "formulated to meet..." :

Controlled Slip Differential, Rear .....GL-5*[5][6]
All Temps......75W-90
Severe Gear 75W-90

5. Synthetic lubricant, GM part no. 12378261,formulated to meet
GM specification 9986115.
6. With complete drain/refill add 4 oz part no. 1052358


I see what you are saying....it is a 'round about' way of implying. I hate BS marketing like this.

darkman
03-11-09, 11:01 PM
The seem to have re-worded by it mentioning: "formulated to meet..." :

Controlled Slip Differential, Rear .....GL-5*[5][6]
All Temps......75W-90
Severe Gear 75W-90

5. Synthetic lubricant, GM part no. 12378261,formulated to meet
GM specification 9986115.
6. With complete drain/refill add 4 oz part no. 1052358

The words "formulated to meet GM specification 9986115" in footnote 5 refers to GM part no. 1237861, not the Amsoil fluid. It is this specific advesrtising ambiguity that I pressed Amsoil on before. (That was covered in that prior thread.)

For record, I think Amsoil is a good product and would not hesitate to use it. I use the GM stuff because I also think it is good and I let the dealer do the changes to make sure there is no confusion about how often I am changing it. In prior threads, we also pretty much established that the Service Techs probably cannot tell what fluid your running.

lollygagger8
03-12-09, 10:15 AM
In prior threads, we also pretty much established that the Service Techs probably cannot tell what fluid your running.

The "grape" smell in GM crap is a dead give away. Even though it smells like doo doo, there is a hint of grape smell to it so the tech will be able to find out. <- oh ya I was dumb enough to take a wiff :vomit:

Twitch
03-12-09, 10:43 AM
Did you smell it after it was in the diff? I couldn't tell when I changed my fluid.

Slithering_Joe
03-12-09, 11:06 AM
I was wondering that too. If the rear was used for a while, could a tech still smell the "grape?"

lollygagger8
03-12-09, 11:22 AM
Smelled "less grapey" after in diff for awhile, but you could still smell it a little....to me at least

That's a great question for Ewill to answer as I'm sure he's changed one or two :lildevil:

thebigjimsho
03-15-09, 01:04 AM
I like the RedLine fluid because it smells like strawberries...

Slithering_Joe
03-19-09, 04:53 PM
After ~3,000 miles on the replacement differential, I was surprised to see how much of a sparkle the gear oil had to it. I have seen oil from diffs with many more miles on them but this was not what I had expected for the mileage it had. The magnetic drain had a ton of ferrous sludge attracted to it as you can see from the crappy cell phone picture below.

http://i189.photobucket.com/albums/z130/Slithering_Joe/My%202005%20CTS-V/031909_134211.jpg

The drained gear oil definitely has the "essence of grape." I feel a little better that I have fresh oil in there for the long haul. We'll see.

darkman
03-19-09, 05:17 PM
The fluid from my replacement differential already looked awful at 500 miles. The first drain is the worst, whenever it occurs.

thebigjimsho
03-19-09, 11:18 PM
The fluid from my replacement differential already looked awful at 500 miles. The first drain is the worst, whenever it occurs.
yeppers.

mpunklil
03-19-09, 11:38 PM
Anybody forked out the cash for the lingenfelter diff cooler? any advantage? i bet you could put an inline filter on it if it doesnt have one...

lollygagger8
03-20-09, 10:17 AM
I'm a big fan of changing out the fluid 2x/ year because of this. It looks like hell everytime.

mpunklil
03-20-09, 01:28 PM
Anybody forked out the cash for the lingenfelter diff cooler? any advantage? i bet you could put an inline filter on it if it doesnt have one...

anyone?