Ok so I did the t-5 swap last winter, ever since i did it there is a clunking noise like something is lose sometimes when i let off the clutch. Its hard to explain, but if u make the car jerk a little bit you can hear it. I bought everything new except a used alum driveshaft. Could it be the u joints? Or what else do you think it could be. The tranny mounts new and thight im not sure.

 

could be U joints or throwout bearing, but that would only do it when clutch is in

 

check the u-joints first but make sure that no exhaust parts/pipes are positioned close to the driveshaft