Grinding/Thunk on Accel and Decel What could it be? (6 Viewers)

[mgriff67]

Hi everyone,

I got my 1994 fj80 not long ago and it’s got its quirks. The big one is like to address now is this thumping/grinding noise that happens on acceleration and deceleration. It only occurs when the pedal is at the very end of its return travel or beginning of acceleration. There is a notable thump that occurs when both accelerating and decelerating. I can’t tell if it’s from the center diff, transfer case, but I jiggled the driveshaft and there wasn’t any play in the U joints. Anybody able to shine some light on the situation? Thanks!


Here is a link to a YouTube short of the noise:

 

[Themcfarland]

I bet ya its either the Joints or you have a loose pinion nut /busted seal/dry gears.
ujoints are typical .
I say ujoints as you are taking the slack out of the shaft when your pedal is where you describe it..

 

[NelsonCruiser]

When checking the u jounts park on level ground and set the handbrake after you put the truck in park before you let off the foot brake. Then climb under the truck and wiggle the drive shafts. This will make sure there isn’t any load in the driveline, preventing them from binding when your trying to wiggle them.

Be aware if your handbrake were to fail the truck will roll a few inches. Be mindful and keep your extremities clear.