when I put my car in drive, the rear end makes this huge clunk sound. like the car slams into gear, but its coming from the diff or rear end. The rear end kinda jumps too. I feel like it has something to do with the driveshaft and the diff but I dont know. Someone please help, thanks.

 

Maybe the differential fluid needs to be changed.

 

Check the driveline components; put the car in neutral and twist the driveshaft by hand and see if you have excessive play. Check your subframe mounts, differential mounts to see if they are still good.

Does it make the same sound going in reverse?

 

it only does it going into drive. I know a guy who used to build fox bodies and said it could be the CV joint, but I dont think our cars have the same kind of drivetrain set-up from what I've read.