on my 86 na my drive shaft use to vibrate so i thought it was the u joints but turns out my driveshafts bolts were loose and allowing it to move a lil. now that i fixed that no vibrations but now it clunks when i acc. such as letting off the gas then accelerate just a lil u hear it. it does it going to into gears and shifting. its getting more frequent and when i twist my driveshaft in nuetrel i hear a slight clunk coming from the tranmission or so it seemed. not from the u joints of the drive shaft itself. i have bought a used driveshaft and was hoping not to have to change shafts. any help would be awesome thanks

 

A clunk between shifts and under sudden acceleration is going to be the front diff mount. It's possible all the vibration caused by the bad driveshaft caused the mount to nuke itself. Try to pry the nose of the diff upward from the rear subframe. If you can, the mount is broken.

 

where is this located? front or rear?

 

On the front of the differential. It's inches from where you were messing with the studs/nuts that connect the driveshaft to the diff's pinion flange.

I have some pictures of the area here: https://www.rx7club.com/2nd-generation-specific-1986-1992-17/pinion-snubber-diff-mount-replacement-convertible-876959/

 

ok thank you very much thread will come in handy. but one more question. should i replace immediatly ( as i have 2 kids am only 20 and have NO time) or can i let it go for a while. i dont drive highway just in town but i do have a heavy foot. so should it be replaced right as this moment or can it wait

 

I wouldn't wait too long. A broken mount is going to put stress on other components. In the mean time, try to gently shift between 1st-2nd-3rd. Rev match any downshifts and go easy on the throttle.

 

rev match is when you down shift and rev a lil bit into gear to equal transmission speed to wheel speed?

 

Yes, which smooths our gear changes.

 

thank again. at this moment the clunks have slowed so i will wait to desent weather to just change the entire shaft and correct any mounting problem.