when i shift hard from first to second or sometimes when the tires break loose in second, a couple times in first, sometimes when its just starting to hook up,i hear feel something knock/bang against the underneath of car. sounds like its underneath or behind me.. brand new tranny and engines mounts so i doubt its that. i was thinking maybe the control arms? i havent replaced them yet. i have welded subframe connectors on the car that make an x through the center with a driveshaft loop. i thought it sounded like the driveshaft maybe hitting the loop from the chassis/ suspension changing angles but it did it a couple time last year so when the car was on the lift installing the supercharger i looked at the drifeshaft to see if i coukd see any marks and i didnt see anything.. anyone have any ideas? sorry for the long post, just hard to explain..

 

did you check your ujoints?

 

yeah.. installed aluminum driveshaft last year and did the u joints then