Engine/Drivetrain Vibration Issues

[apardal]

Hi! My on-going project listed in the projects sections is giving me some head aches...

I have a problem left to solve that is an excessive backlash (with a clunk sound, but not the same as the tomei lsd) from my rear end that I think comes from the half axles, but I'm not sure. The ring and pinion (4.77 were installed by the book and had no excessive backlash, new bearings, etc.

This clunk sound that suggests excessive half axle backlash is heard when I'm changing from lightly tapping the accelerator or not accelerating at all. It will bounce back and forth until I decide whether to brake or push the throttle a little harder.

Along with this, is a massive vibration that appears when I decelerate and the car rolls in gear at 3000 rpm or so. Don't really know whats wrong and if it is related to the backlash.

I have prothane bushing kit and greddy coilovers that don't help at all with these vibrations, but I think this is out of the ordinary.

I also have tried another propeller shaft to check the vibration issue, but it was exactly the same (although I'm not sure if this prop shaft I used was in good condition).

The clutch release fork (installed new 2 years ago) was also uninstalled a installed again with a lot of MP grease to see if the problem came from there.

Let me know your thoughts.