2012 Chevy Camaro ZL1 auto – TSB (PI0137C)

@julery Your dealer should have a list of every single TSB on the Camaro, including the TSBs specific to the ZL1. I’d recommend calling and asking the service manager to send it to you.

Noise in rear diff while turning is most likely the limited slip differential clutches alternately grabbing and releasing. This is usually a sign of contaminated or worn out gear lube. GM factory fill gear lubes are nothing but cheap stuff. Weather its new car or not makes no difference, the gear lube is the problem.

They have countless bulletins out over the years dealing with limited slip noise/chatter/banging etc in every model. I had to have the gear lube changed 2 times on my CTS with posi because it make noise when turning. I made them install AMSOIL Severe Gear 75W-90 back in May of 2009 and I have NEVER heard a noise again, nothing. Its always the gear lube but GM is stubborn and continues to use low-bidder lubes. Get rid of the GM brand gear lube and use a good synthetic like AMSOIL, Royal Purple, Red Line.

Btw – My brand new 1970 Chevelle SS454 did the very same thing, been a positration nuisance since they outlawed whale oil as a additive in gear lubes.

PI0137A: Rear Axle Chatter Type Noise on Low Speed Turns – (Feb 24, 2011)

Subject:

Rear Axle Chatter Type Noise on Low Speed Turns

Models:

2010-2011 Chevrolet Camaro

Equipped with Limited-Slip Differential (RPO G80)

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This PI is being revised to add the 2011 model year. Please discard PI0137.

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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

Important: Prior to adding the limited-slip axle additive, the bottle MUST be shaken vigorously for at least one minute to mix the additive thoroughly, then immediately poured into the differential.

Drain and refill the rear differential with new fluid, GM P/N 89021677 (in Canada, use P/N 89021678) and additive, GM P/N 1052358 (in Canada, use P/N 992694). Refer to the Differential Oil Replacement procedure in SI.

Once the differential fluid has been changed, the vehicle must be driven in eight tight figure eight maneuvers to heat the fluid and allow the additive to be worked into the clutch plates

Btw – the letter on the end of the bulletin number just indicates a new revision and as you can see they will do it every model year but never fix the root cause, inferior lubricants.

Good stuff @Z15… good stuff indeed!