so heres the deal, the car grinds and whirrs under deceleration and in neutral but not acceleration, and not in reverse.
the sound appears to be coming from the rear end, maybe the diff., its not a slight noise, its very harsh.
i out the car up on jack stands and same thing, but with the car off, you spin the wheels and get a light *"thud-thud-tud"* from the passenger side wheel, am i dealing with a bad halfshaft here? or is the lsd i bought junk? maybe a bad wheel bearing?

its a 88' n/a with a tII LSD swapped in

 

bump, some help anyone?

 

ive changed the oil in the diff. and there was no metal in it, so i dont think its the spider gears. it causes enough resistance to slow down the car, mostly at very slow speeds, but you can feel the resistance in the rear passenger wheel . some one help me out..

 

could a bad CV joint in the half shaft. does it thud once per rotation? if not, then it's probably bearings or something else. if so, I bet it's the CV joint.

 

no it thuds quite a few times per rotation, any idea on what bearings it may be?

 

uh yeah, the wheel bearings??? you could get under the half shaft and listen for the direction it comes from, that will tell you if it's in the wheel assembly of in the diff

 

well the hub has no play so i dont think its that.. sounds like it could be a pinion bearing. damn.

 

so today the front oil seal blew on the rear end near where it bolts to the driveshaft, oil EVERYWHERE, entire underside of the car about 2/3 the way up the car, even the rear bumper was covered ..heh.. atleast now i have an idea of what it is. so to keep the n/a tranny andn/a drive shaft i swapped out the spline from my n/a to the tII diff., which apparently screwed things up, so DONT try that one at home. so im guessing i will be replacing the front pinion bearing, or whatever else is broken, oil seal and getting the N/A bolt pattern machined into the TII flange. goes to show, do things right the first time.