Groan in my rear end

[LITTLEELVISDAN]

Well for the last couple of days I have been hearing a groan in the rear end when turning left or right. Sounds like a out of round tire scuffing the inner fender well... womp womp womp. I know its coming from the rear diff. I took it in to the dealer and they called me back and said they have a TSB on this and it requires a rear diff flush, and addiing some additives.

Is there really a TSB or are they putting a band aid on a failing rear diff?

History of diff......

Had leaking rear diff at 6k and had dealrer replace rear seal with factory seal( I would assume you would drain the fluid and replace with new at this point)

At 28k had dealer replace rear diff seal with the new GM corrected rear seal. ( again I would assume a fluid change at this point again)

at 32k groan appears in the rear diff.

[CIWS]

There was a TSB on the CTS-Vs diff about a "growl during low speed turns" I had them perform it three times on my CTS-V (36K miles). It required draining the diff fluid, replacing it, driving the car for approx 10 min to get it warmed up, then draining that and replacing it again and lubing. My groan seemed to come back about every 13-14K miles, but never had a whine and still the original diff when I traded at 36K.

They were not supposed to drain and refill the diff fluid when performing the pinion seal recall. Only replace whatever was lost. (top off)

[RightTurn]

Ah, the "parking lot growl", I know it well. Replacing the fluid fixed mine.

And I just wanted to be included in a thread with such an epic title.

[LITTLEELVISDAN]

Thanks all, I had thought the STS-V diff was a different rear than the CTS-V and had hoped they didn't share the same issues. BUT...

[CIWS]

Subject: Shudder Or Bind On Low Speed Turns - keywords axle differential
groan growl moan noise rear slow vibration #PIP3152J - (02/09/2007)

Models: 2004-2007 Cadillac SRX, CTS, CTS-V
2005-2007 Cadillac STS
2006-2007 Pontiac Solstice
2007 Saturn Sky
Equipped with Limited Slip Differential (RPO - G80)

This PI is being superseded to update recommendations. Please discard PIP3152H.

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:
Customer may comment of a shudder or bind from the rear of vehicle on low speed turns such as parking lot maneuvers on vehicles equipped with G80 limited slip rear axle. This condition may be more noticeable with the vehicle at operating temperatures.

[dhemrick]

Wow.... what timing. My car just started doing this and I was wondering what was happening. This exactly describes it.

Good to know it is a quick fix. But it concerns me that it may come back.

[Florian]

Originally Posted by LITTLEELVISDAN

Thanks all, I had thought the STS-V diff was a different rear than the CTS-V and had hoped they didn't share the same issues. BUT...

CTS(v), STS(v) and SRX all share the same crappy Getrag diff.....

Flush, drain repeat.


F

[dhemrick]

I just called the dealer to set up an appointment and said that they are well aware of the issue. He said that GM wants them to do the "flush, drain, repeat" routine, but he said the real problem is the clutch plate. When they see this issue, they just go ahead and replace the clutch plate because flushing the differential is only a temporary band-aid, not a solution.

He's checking his parts department to make sure they have the proper parts for the V (to make sure if they are or are not different from the regular STS). I'll set up an appointment to get it fixed depending on parts availability. He said it takes about 3-4 hours for the job.

[dhemrick]

Just to follow up.

I took the car in today to get the rear end "binding" issue fixed.

They resolved the issue, but I am kind of annoyed at the reason this occurred. The dealer told me that the "build sheet" for the STS-V does not show that it has a limited slip differential. Therefore, when I had the pinion seal recall work done, they only put back the differential fluid, but not the "limited slip differential fluid". The fix was to drain the differential fluid and replace it with the proper fluid.

I am not that familiar with the different fluid requirements of limited slip differentials as opposed to regular differentials.

I didn't have time to really quiz them on it, but the more I thought about it after I got home, the more I am becoming concerned that
a) they just went by a "build sheet" instead of actually looking at the car, and
b) I drove this around for probably 3 months and about 4000 miles with this incorrect fluid in it.

They insist that no damage was done, but I am not so certain. I am also wondering if this may be the cause of other people's rear differential "binding" issues.

This dealership is normally top notch and despite this mistake took great care of me today and did have the courtesy of letting me know what occurred rather than covering it up, but I am a bit concerned that this happened and what it could have done to my car for the long term.

I would be interesting in hearing your thoughts, particularly from some of the dealer reps on here or from people very familiar with limited slip differential maintenance.

Thanks,
Dale

[LITTLEELVISDAN]

I'd agree.. Mine was worked on twice before the binding showed up. To which they only topped off the fluid so I m sure ther e was a little less limited slip additive in there when it started. Problem fixed now that they flushed it.

[CIWS]

I had the recall done in February and so far I'm not growling.

No STS-V was/is ever built with anything other than the limited slip diff. So again it simply demonstrates the frustration we see as V owners and some of these dealerships service departments not being familiar with the V series cars and their particulars

[Cadillac Tony]

Originally Posted by dhemrick

The dealer told me that the "build sheet" for the STS-V does not show that it has a limited slip differential. Therefore, when I had the pinion seal recall work done, they only put back the differential fluid, but not the "limited slip differential fluid".

This happens more than I like to hear about. For whatever reason, cars that have the G80 limited slip standard cause a lot of confusion in some Service Departments. The Standard Procedure is to print a list of options on the car and look for G80 to see if the additive is needed. CTS-Vs and STS-Vs have G80 standard, so it doesn't show up on the build sheet- the Tech assumes it isn't there, and doesn't use the additive.

There shouldn't have been any damage done. The additive is there to allow the plates to slip on each other instead of grabbing in extremely tight maneuvers (like a parking lot), so the "parking lot growl" is just the sound of the clutch packs momentarily binding due to the lack of additive.

We've been replacing the clutch plates in diffs lately instead of replacing the whole thing, so rest assured that it could be done easily on yours if it turns out the clutch plates are worn.

[dhemrick]

Thanks, folks! I really appreciate the information, especially you Tony. I just wanted some reassurance from another dealer that what they were telling me was not a load of BS and that there is no permanent damage.

I drove the V from Raleigh to Atlanta today and all around Atlanta today with no further occurrences of the "low speed maneuver growl" or binding. That seems to have solved the problem.

Again, thanks!

[LITTLEELVISDAN]

WELL! The groan came back about 3 weeks after having the TSB performed. Took it back to the dealer yesterday and to my suprise I got a call today saying my new tires were mounted and balanced and the oil had been changed. They told me to come pick up the car. They said they had ordered a whole new rear differential. I said you mean new clutches? They said nope a WHOLE NEW DIFF. I said why? they said they didn't want to screw around with it any more especially since I had the fluid leak because of the seal TSB and they don't know how long it went with low fluid before we cought it. I was happy to say the least.

So far
TSB for rear diff leaking - replaced seal with old version seal
TSB replacement of old seal for new design seal
TSB for rear groan - flushed and replaced fluid
Back in for rear groan - ordered whole new diff

This should fix it.

[LITTLEELVISDAN]

UPDATE*** went to pick up my car with the new rear dif in it and was suprised to hear a strange noise when shifting into drive. It sounded like a marble in the bottom of the center concole rolling back and forth when I let off the brake and applied the break again. I backed it in the bay and had the service rep try it. he got in as I stood outside and he started to get funny looks on his face. he got out and said he had heard nothing like that. The gas light was on (I took it in that way) so he asked me to go get some gas while he got the tech. Driving out of the dealer the car felt a bit sluggish but nothing to alarming since it was cold. Step hard on the gas and I could hear the transmission and exhaust like there was a big hole in the floor under the center console. QUITE LOUDLY... 1 block to get gas and the thing smelt real hot underneath. got back and the tech took it for a spin and to my suprise they took immediately to the bay and up on the lift it went. They sent me off with the same loaner that had not even been processed frome me bringing it in. I also noticed under the front pass door where they gouged the bottom of the rocker from the lift. It also looks like thay had done it before because there was touch up paint on the bottom edge of the same door.