Is it my differential or u joints?

[Joel]

Okay so me and my friend were having a little race my car has had some problems with the rear end it hops real bad at a launch unfortunalty he wanted to race from a dead stop my idiot self went for it so after we raced i heard this clunking kind of noise i think i blew out the whole rear end but im not sure if its just my u joints or the spyder gear because its still going through gears perfectly but when im just coasting it sounds like its hitting against something Im pretty sure someone has went through this same problem with a 2001 trans am ram air Please help me not really sure whats the problem

[cammed goat]

Put the car in the air and spin the rear wheels back and forth. While doing so, check to see if the driveshaft is wobbling around. Could be a U-joint or, worse case scenario, pinion bearing. Also check to see if there is any wetness around where the driveshaft goes into the rear end. If the wetness is severe, my guess would be the pinion bearing is shot.

[35th-ANV-SS]

Wheel hop destroys rear ends. I'm putting money on it being the rear end. Hopefully for you though it isn't.

[Knight]

I'm with Jon. But I'd do as Rich suggested, which should tell you where the problem exists. You could also pull the rear diff. cover and do a visual inspection.