Ok Ive only had my 280 for a few weeks but the rear end is so freakin loud! I took up the carpet and put some padding down but its still really loud. Is this commen for z's or do I need new shocks???

Sounds like you need a different differential. There is supposed to be some padding under he carpet. Which helps with road noise, but if you have gear noise that is loud , not good. Gary

What kind of noise are talking about? Where do you think it's coming from?

Its like when I go over bumps and stuff. The sound is more of a... slam!!! Sound. Im guessing its my shocks but not sure... Oh I have one more thing thats been on my mind as well. My 280 is an auto and when i go from park to reverse it make thing clunk sound pretty hard too.

Sounds like your front differential mount.