Hey guys,

Lately I have been noticing that when I put my 08 XK into reverse, I hear a distinct "thunk" coming from somewhere underneath the car just as I start to back up. I think it is somewhere in the chassis/suspension, vice the transmission, especially since the "thunk" occurs just as the car is starting to roll, and not when I actually shift her into reverse.

Any thoughts?

 

A quick suggestion; try NOT setting the electronic parking brake and see if the clunk is still there upon backing up. If the noise is still there, at least, this would eliminate the parking brake release from the equation.

 

Did you find any resolution on the "thunk". On my XKR 2008, it seems like there is a slight backlash somewhere. When I let off accelerator quick, I can get a sound like a thunk, also at low speed. Any ideas on what this is all about. I had rear unit replaced last year, under warranty, due to shaft seal and bearing problem on cross shaft. It also seems like something isn't quite tight. I have no other symptoms. I do not drive car real hard, so at 30K, there should not be issues.
Thank God, I have a good extended warranty if it comes to diving into the drive-train.
Any ideas appreciated.