I've read all the comments about worn out parts causing the rear clunk but mine is just the opposite. I have a 1978 280Z that made no rear clunking noise what so ever with the old rubber bushings. I just replaced the mustache bar, inner control arm and sway bar bushings with energy suspension poly and now when getting on and off the clutch I get the clunking. I used lots of grease and I torqued all the bushings down to spec. When I dropped my diff down, I did notice a piece of thick rubber fell off the top of the diff ander the arrestor strap. I put it back in where I thought it should go. Is this a factory piece (it looks kind of like a piece of tire rubber) or did a previous owner put it there to eliminate the clunk in the first place? I now have a better handling car but also have the dreaded clunk!

Thanks,

Dan

Seems like your rear differential mount has failed.

Yeah these things were a piece of garbage on these cars

Thanks! Great pics!

I luv Maryville. Right down the "I'll Kill Ya" highway!

Arizonacar.com makes a billet aluminum differential mount. I don't personally own it, but it looks really nice. I plan on buying it when I get to the rear end.