Im posting this for my friend whos got an 1987 IROC:

"I got a used rear last year.....started to have a clanking sound from mid to back of the car a few months later, the clanking progressed through the months, eventually a loud grinding sound came out of no where and the car would not go into gear what so ever.....in reverse or drive it doesn't even move."

He thinks it might be a U-Joint, can you guys give us any advice on what you think it is? Thanks.

 

take the diff cover off

 

It's not the u-joint, it sounds like the pinion gear or ring gear has chewed itself up. It is common on older rear ends where the pinion nut backs off and loosens up because of vibration and age, and the pinion gear and ring gear are out of alignment and self-destruct. Junkyard rears should always be opened and freshened before using.

He will need a new ring and pinion set and maybe new bearings.

 

Thanks, Ill tell him about that. Have any idea of what that would cost him?

 

i gotta agree with onefastgta... thats what i thought when first reading the post.