well ive noticed that behind me there is a weird knocking sound, its not always there and it usually pulsates (sp) when it is there... not exactly sure where it is... over the weekend i replaced 1 rotor and 4 break pads.

 

Could be that the backlash in the rear is off. Put it up on a lift or jackstands, grab the back wheel, and shake it. Normally, if the backlash is off, you'll hear a rattle.

 

Changing fluid in the rear is another awesome fix for noise. My rearend was making the WORST noise you could imagine when I first bought the car. Especially when turning corners. I changed the fluid and put a bottle of limited slip additive and its purrrfect. I've been blasting it for over a year now with 1800 rpm launches on Nittos. I thought it was toast at first.

Another possibility is a bent axel.

 

Could it be the drivshaft? I get a little pulsating noise and Im gunna swap out the driveshaft and see if thats the problem. I think they have been known to be unbalanced.

Chris

 

i think its brake related, when i step on the brakes it goes away, but it makes one more thud when i do step on the brakes.

 

whats the back lash?

 

Backlash is the how they space the gears. The Sprocket to the Pumpkin. If this is off then it will not seat correctly and could clunk. But I think you are on the right track. It is brake related. Have you taken the wheels off to see if you can obviously see something wrong?

 

Backlash is when the gears aren't meshing quite correctly. I've had to get the backlash in mine re-adjusted twice.

 

I know this sounds stupid but are you 100% positive that your wheels are tightened up all of the way