I have a 2002 C4S manual trans with 42k miles. I'm hearing this high pitch sound coming from the rear while on 3rd gear. I've had 2 mechanics, one independent Porsche shop and the other was a Porsche dealer and both of them said there's nothing mechanically wrong with it. The car drives fine but it is so annoying that it forces me to get out of 3rd right away. I'd like to get to the bottom of it while the car is still under extended warranty. I'm asking if any C4S owners have this issue as well or if anyone have any idea on what could possibly be the problem.

 

My guess is its the pion gear baearing in the transmission....I had this problem also. Are you getting the sound when you are on the throttle. Also, do you get it in other gears as well? The bad news is you can either live with it or have the transmission rebuilt. For me the rebuild fixed it. You could just do the bearing but by the time the whole transmission is out and the work required, you might as well do the whole thing. Again, this is my guess. Interesting to see what others say

 

Hi lowpue, yes I'm only getting it on 3rd gear and only when I'm on throttle. And it's only happening on 3rd gear. We're getting yours on other gear as well? I'm worried that if I let it go now that it might turn into a bigger problem later on. Will wait for other comments. Thanks for the feedback.

 

I had it in all gears so its not likely the pinion bearing but it may be a third gear bearing of some sort. Probably will need to be fixed. My symptom was difinitely whenever I got on the throttle and in all gears.