vette blue

Hi, My 71 small block, Muncie 4 speed goes clunk everytime I shift from 1st to 2nd and 2nd to 3rd unless I really slowly let the clutch out.
I changed the big rubber cushion mount on the differential and this took away the clunk from a standstill in first gear but it is still clunking in the other gears. I haven't checked the tranny mount yet but the motor mounts are in good shape.

What should I be looking for?

blue70ray

Your u-joints could be worn and have some play to them. This might be the sound you hear...

hutch70

vette blue

Clunk only happens when clutch is released into 2nd and runs quiet until shifted into 3rd. Shifts quietly into 4th.
Wouldn't u joints be a constant noise?
Also u joints were inspected and passed. Is there any other part that could be the culprit?

blue70ray

You would only here the noise when you initially shift into gear and not while in gear. Did you have all the u-joints checked including the half shafts?

vette blue

I know he checked the half shafts and drive shaft. How would I know if they are worn if I check them myself?

blue70ray

That I'm not sure of. I had mine replaced when I started hearing the noise. You might be able to move the shafts if they are really worn but I don't think they are that bad. Oh, and when I had mine replaced I also had the main and half shafts balanced. I figured while they were off it was worth the extra doe.

spanky01

the rear diff if it has a lot of play in it will cause a clunk / even more so if your yokes going to your half shafts are worn out too this sound will be amplified by good but worn u joints

croaker

My clunk Was a bad U-joint could only find it by taking off the half shafts mine would clunk creeping in first I thought it was slack in the rear end