ZR-1 Net Registry Forums - View Single Post - Rear-End Knocking

tomtom72 · 12-20-2005

Just a thought from left field...if the bushings on the "bat wing" &/or the control arms are okay...big if, could one of the shocks have come loose somehow???

Another thought: how about checking the U-joints and stub axels for play. I know they were a source of minor trouble on the C3's. Another thought, have you been keeping up with the rear gear fluid changes?? When the fluid looses it's lubricity the clutches have a tendency to "hang up" when going around corners first and if you leave the fluid long enough they will hang up even in a straight line???

I know my C3 was a bit of a PIA when it came to the rear fluid change intervals...finally I gave up & started changing it every 10K miles. GM fluid + GM additive every yr solved my rear noise problems.

Good luck & Gingle Bells!
Tom

12-20-2005	#3
tomtom72 Join Date: Dec 2004 Location: Jacksonville, FL USA Posts: 4,609	Re: Rear-End Knocking Just a thought from left field...if the bushings on the "bat wing" &/or the control arms are okay...big if, could one of the shocks have come loose somehow??? Another thought: how about checking the U-joints and stub axels for play. I know they were a source of minor trouble on the C3's. Another thought, have you been keeping up with the rear gear fluid changes?? When the fluid looses it's lubricity the clutches have a tendency to "hang up" when going around corners first and if you leave the fluid long enough they will hang up even in a straight line??? I know my C3 was a bit of a PIA when it came to the rear fluid change intervals...finally I gave up & started changing it every 10K miles. GM fluid + GM additive every yr solved my rear noise problems. Good luck & Gingle Bells! Tom __________________ 1990 ZR-1, Black/grey, #2233, stock. ZR-1 Net Reg Founding Member #316 & NCM member