When I accelerate from stop with my car it shakes alot. When speed is up it's ok though. I've changed alot of parts that I suspected could have caused this. Like engine-, transmission- and torquearmbushings. So all that is left is either worn u-joints or diff. Also I've noticed that when cornering hard and trying to let the rear loose it often just spins one wheel. On straight it always spins both wheels though. So what do you guys think?

 

Sounds like your shake could well be a dinged or out of balance driveshaft versus the rear diff. As for your rear if you suspect your posi is bad just jack up one rear wheel and see how much effort it takes to turn the wheel with the car in neutral. If there is little or no resistance your posi is gone.

 

Ok, thanx man! I'll try it as soon as I get the chance.

 

Okay the posi seems fine coz there is resistance.

The shake I mentioned earlier isn't just something vibrating - which I would imagine an out of balance shaft would feel like - but there is actually play somewhere in the drivetrain area. So a launch type acceleration is really jumpy from stop or otherwise slow speed. It's worst when I do a "kickdown". It feels like the whole drivetrain is about to come apart. If I press it more gently it isn't as bad.

I have put in new engine-, transmission and torquearmmounts because I thought these were the cause of it all. But replacing these didn't help a bit. And I have also had it to a mechanic and he checked the rear u-joint spicer and said it wasn't worn enough to be causing this.

So what could cause this play??