I just purchased a used 2000 XK8. Great power and tons of fun.
But recently I have been having what sounds like a slipping problem. If I come to a rolling stop and try to accelerate I have a delay then a loud clam into gear. I checked trans level and its ok. I checked all the U joints. All good. Best guess is that the rear axle is the cause. Is there a way to troubleshoot slippage or is there another thing I am missing?
Any help would be great
Thanks

 

What you are missing may be the failure of the transmission A drum. Is there also a lag when shifting from P or R into D?

 

It shifts perfectly into D R from P... I can hear the slamming near the back end of the car. I thought the drive shaft was slipping originally. But I had it on my lift and all the noise comes from the rear axle area

 

Check the universals on the half shafts. Just grab one with vise grips and try to rotate, then the other. Look for play in the joint. They are often not lubed, the only grease fittings on the car.

 

All the U joints on the half shafts and drive shaft are perfect and lubed

 

Did you check the transmission mount?

 

Also check the Rear Suspension mountings:


(click on the image to enlarge it)

The 'A' Frame bushes (RH side arrowed in red) are a regular fail. Monostrut bushes (RH side arrowed in blue) can also fail allowing rotational movement of the rear suspension as power is applied.

Graham