Rear diff

[winterboy8]

I guess I lucked out for now, as I didn't experience any noise or chatter while turning. I hope my new diff doesn't cause either of these to happen.

[Cabinetman]

Originally Posted by ZMEnow

I have lived with this for a couple of years now and coming up on 9k miles the howl has widened from 68-72 mph in 5th only to 63-73 in 5th and 4th, so the lash is getting worse. I also would like to hear your success of having the pig replaced and if it's better or worse as the risk of worse have stopped me from doing it..

This is my concern as well. The whine is not terrible in my car at this moment and I'm concerned that any "fix" the dealer might apply will cause more problems in the long run. I will still likely try to get the whine fixed, but I realize I may have to take the car in multiple times to get it right.

[winterboy8]

Not that this matters in my case, but this is an excerpt from the owner's manual under the break-in section:

- Should the vehicle be used for racing or competitive driving (after break-in), the rear axle lubricant must be replaced before hand.

[winterboy8]

Woohoo, I got my car back and it's nice and quiet now. I asked the service manager and called GM to ask if there was a break-in on the new rear end and both said no. As much as I really want to try out LC and NLS, I think I'll put a few miles on the new diff before I go launching from a stop. I hope this fix works and no more rear diff issues for this guy.

[Cabinetman]

Originally Posted by winterboy8

Woohoo, I got my car back and it's nice and quiet now. I asked the service manager and called GM to ask if there was a break-in on the new rear end and both said no. As much as I really want to try out LC and NLS, I think I'll put a few miles on the new diff before I go launching from a stop. I hope this fix works and no more rear diff issues for this guy.

I'm glad to hear they got it fixed. I will be taking my car in soon to have it looked at.

[Sven59]

Originally Posted by ZO6 Bryan

Your info is old. The TSB for the Camaro SS was replaced by PIO137C. Disregard the old one. The new TSB tells them to replace the diff fluid with the same fluid as the ZL1. So not that different after all. But they also are supposed to replace the seals because the old ones are impregnated with the old fluid.

2012 Chevrolet Camaro | Camaro VIN F Service Manual | Document ID: 2740658
#PI0137C: Rear Axle Chatter Type Noise on Low Speed Turns (Excluding ZL1) - (May 11, 2012)

Subject:Rear Axle Chatter Type Noise on Low Speed Turns (Excluding ZL1)

Models:2010-2012 Chevrolet Camaro (Excluding ZL1)
Equipped with Limited-Slip Differential (RPO G80)

Attention:For 2010 and 2011 vehicles built prior to August 25, 2010, if the chatter noise you are experiencing occurs only in Reverse while making a turn, please review the latest version of PIC5424.
This PI is being revised to add an Attention statement and update the Recommendation/Instructions. Please discard PI0137B.The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern


Some customers may comment on a chatter-type noise from the rear of the vehicle while making low speed turns.
This condition may be caused by a slip/stick of the posi-traction clutch plates. As the plates slip and stick, a jumping or jerking feel occurs, accompanied by a chatter noise.

Recommendation/Instructions

Caution: The rear axle seals must be replaced. The original seals are not compatible with the new fluid.

Replace both rear axle shaft seals with GM P/N 22798805 and drain/refill the rear differential with new fluid, GM P/N 88862624 (in Canada, use P/N 88862625). Refer to the Rear Axle Shaft Seal and Differential Oil Replacement procedures in SI. This fluid includes a limited-slip additive (friction modifier) already added. DO NOT add any limited-slip additive (friction modifier).
Important: Please advise the customer that once the differential fluid has been changed, it may take as long as 805 km (500 miles) for the lubricant to fully penetrate the limited slip clutch plates. During this period some chatter may still be felt on initial startup while making slow turns until the rear differential fluid warms up.

Thanks for the update,

It just helps make the point that ZL1 owners need to keep their dealers informed. The first time I brought mine in for the rear noise the service manager brought out the old Camaro TSB and said they were going to perform it. Luckily I had read here about the ZL1 TSB and asked him if he could find it. He came back with the ZL1 TSB and apologized. If they would have gone ahead with the original TSB I would have had the wrong fluid.



I noticed in the new one you provided it says Excluding ZL1 3 times, I am guessing because of the confusion between the TSBs.



2012 Chevrolet Camaro | Camaro VIN F Service Manual | Document ID: 2740658
#PI0137C: Rear Axle Chatter Type Noise on Low Speed Turns (Excluding ZL1) - (May 11, 2012)

Subject:Rear Axle Chatter Type Noise on Low Speed Turns (Excluding ZL1)

Models:2010-2012 Chevrolet Camaro (Excluding ZL1)
Equipped with Limited-Slip Differential (RPO G80)




In the Base Camaro TSB it seems the problem was the fluid they were using since they switched to the ZL1 type fluid and had to replace the seals due to possible impregnation/deteriorization. In the ZL1 TSB it seems to be a problem of something in the fluid they want out and no seal replacement.




Caution: The rear axle seals must be replaced. The original seals are not compatible with the new fluid.

Replace both rear axle shaft seals with GM P/N 22798805 and drain/refill the rear differential with new fluid, GM P/N 88862624 (in Canada, use P/N 88862625). Refer to the Rear Axle Shaft Seal and Differential Oil Replacement procedures in SI. This fluid includes a limited-slip additive (friction modifier) already added. DO NOT add any limited-slip additive (friction modifier).
Important: Please advise the customer that once the differential fluid has been changed, it may take as long as 805 km (500 miles) for the lubricant to fully penetrate the limited slip clutch plates. During this period some chatter may still be felt on initial startup while making slow turns until the rear differential fluid warms up.


I just hope other members that read this go to their dealer with a good knowledge of the situation and the right TSB.

[djnice]

Originally Posted by ZMEnow

I have lived with this for a couple of years now and coming up on 9k miles the howl has widened from 68-72 mph in 5th only to 63-73 in 5th and 4th, so the lash is getting worse. I also would like to hear your success of having the pig replaced and if it's better or worse as the risk of worse have stopped me from doing it..

Same story here.

[blk 2013]

when I took mine in they said it was the tires (B.S.) but at least I started a paper tail that I can refer to as it gets louder.

[himmy33]

Is this covered if the car is no longer under warranty?

[Sven59]

Factory I doubt it, a voided warranty probably a good chance. It would be hard to attribute the backlash being off to engine mods. The back lash would almost have to be from basic setup.

[himmy33]

Sorry i should have been more specific. The car is stock. I believe it may be past the three year warranty though. Or is the drive train warranty longer than 3 years?

[Sven59]

5 years and 100,000 for the driveline.

[himmy33]

Great!

[himmy33]

So my issue is the car vibrates when I get off the power in between 70 and 45 MPH. It gets worse the faster I am going when I let off. I am pretty sure this is a backlash issue but for some reason I can't find the TSB for it now. Any help would be appreciated. Thanks!