Need help diagnosing strange noise
I have a 91 ZR-1 with under 25k miles, I keep hearing a strange noise when I drive the car. It is coming from right side and I think the rear of the car. It's not real loud and I hear it better when I am against a wall and the sounds reflects back. It sounds almost like a baseball card in the spokes of a bike or one of those game wheels you spin at the board walk. It does it only when the car is moving and stops when you depress the clutch. it does it in all gears.It's pretty steady and doesn't speed it up when I accelerate. Any ideas would be appreciated,
Thanks
Todd
Welcome to C4 ownership.
The fix is rather simple, too... It's rust in the rear stub axle.
The simple fix is to remove the wheel and the nut keeper, and try to flood the stub axle with something like PB Blaster. If that doesn't work, the stub will have to come out, be scrubbed off, reinstalled with some anti-seize to keep it from rusting.
Also, age vs mileage thing, you may have a dry ujoint. I would check them... tight is one thing, but dry is another... And they are not greasable. That's a labour intensive fix, too.
Which leads to a general suggestion, when replacing ujoints on these things, take them apart, remove the crap grease they include and regrease with a good heavy synthetic - Mobil 1, Lucas, Valvoline... take your pick.
https://www.corvetteforum.com/forums...-fixed-it.html
Hope you can help...
bgo ahead click click 
seems to be a terrible noise due a serious breakdown, instead it is just a grease lack
Welcome to C4 ownership.
The fix is rather simple, too... It's rust in the rear stub axle.
The simple fix is to remove the wheel and the nut keeper, and try to flood the stub axle with something like PB Blaster. If that doesn't work, the stub will have to come out, be scrubbed off, reinstalled with some anti-seize to keep it from rusting.
Also, age vs mileage thing, you may have a dry ujoint. I would check them... tight is one thing, but dry is another... And they are not greasable. That's a labour intensive fix, too.
Which leads to a general suggestion, when replacing ujoints on these things, take them apart, remove the crap grease they include and regrease with a good heavy synthetic - Mobil 1, Lucas, Valvoline... take your pick.
thanks for the info. my only concern is the noise goes away when you depress the clutch. clutch and throw out bearing ,pilot bearing and flywheel all were replaced about 6k miles ago.














