I have an issue with a clunking in the front of the 997.1 Turbo. Now this mostly happens when I back up and the steering is near lock. It will clunk and lurch a bit and then sometimes when I go forward after this it will clunk again (but usually much less) and then it is OK.
Now I have read many cases where people say this is normal and is due to the geometry of the suspension and the noise comes from the springs moving in their mounting.
So what it is? I knowe Porsche has a technical bulletin on the mounting hardware for the spring on this but they say it is for a "Clicking". This is a strong clunk.
So what are the symptoms on a CV joint? Bad differential? The dealer says he never heard of the springs causing a clunk yet it's all over the forums.

Help!!
Thanks! Tom

 

I have heard mine doing the spring clunk before. But the lurch you are describing makes it sound like more of a diff or axle issue.

 

I have issues with my front diff but haven't noticed anything while backing. I get the clonking noise when driving in low gear and lifting off the throttle quickly. And I think I see what you mean with the "lurching": feels like something is loose underneath and "swinging" from side to side.

Hope that is not the case for you since a replacement diff is $10K :S

 

A bad CV joint is usually a metallic clicking sound when the steering angle gets large, and it will do it at all speeds. The clunk could also be worn out tie rod ends in the steering, or lower ball joint or control arm bushings allowing things to move around.Maybe even wheel bearings?