Whitey13

Ok, I've noticed a something that has just started happening lately. When my car sits for a bit, it makes a grinding noise like metal on metal from the rear. Either forward or reverse. And it only makes the noise for about a 100 feet. It does it with the motion of the rear wheels. For example, the wheels turn 75% and then it grinds, another 75%, then it grinds , etc, etc. Then it stops. It's has me baffled. I don't know if it matters, but the guy who had the car before me put a spool in the posi so she is locked tight. Any ideas?

n2ceptor

A spool permanently locks both axle shafts together so that both rear tires will always turn at the same speed. .... A spool is for going in a straight line, not for daily driving.....

Whitey13

Yeah I know that, it chews through tires pretty fast. Do you think that has anything to do with the noise thats developed?

Whitey13

Oh and btw, I know 4 people who drive their vehicles daily with spools (one is a 4th gen camaro and he is going on 6 years). Not trying to be a smartass, just saying

Hal Fisher

Have you changed the oil back there lately? I know the regular limited slip hub needs the special GM limited slip oil or else it makes all kinds of grinding noise.

Hal

Whitey13

It's not the factory rear end but I should probably change it anyways. Cheap insurance. I'll let ya know if that quiets it down. Thanks man.

Injuneer

Does "sits for a bit" mean long enough for the brake rotors to start to get a surface coat of rust?

Whitey13

I suppose I should have clarified what I meant by that. It makes the noise if it sits overnight for example. I'm gonna tear the rear apart tonight or tomorrow and I'll let you know what I find.

Whitey13

One of the bushings on the control arm had shifted causing it to rub. Put a new bushing in and noise went away.