Rear drivetrain noise - 986 Forum - The Community for Porsche Boxster & Cayman Owners

tylka · 07-07-2010, 05:39 AM

97 Boxster with Tiptronic transmission is making a noise while making left hand turns. The car will not create the sound in right turns. It sounds like it is coming from the right rear and almost sounds like splines of the axle grinding (best example I could think of) clunking like. Usually have to be accelerating or making a quick left turn to produce the noise. I have taken it to a shop I trust that does general maintance and tires and they inspected everything and said that the rear bearing doesn't have play, the C.V.s seem like they do not have excessive play, and all the bushings are tight. Any ideas on what this could be? Thank you for the help.

tylka · 07-08-2010, 08:37 PM

If the CVs are bad, where is a good company to purchase new one from for the tiptronic gearbox?

Boxtaboy · 07-08-2010, 09:45 PM

I had that problem except that it only happened on right turns under power. Turned out it was a worn out motor mount that caused enough driveline disturbance that the grinding showed up in those conditions. New motor mount fixed the problem. This happened to my car at around 60k miles. My car's a manual though.

07-09-2010, 12:48 AM

There are several situations that can create rear drivetrain noise. It the gears have been quiet and began to howl, they are probably worn or wearing. It is a possibility of the pinion bearing preload has lossened. The pinion spins is a common situation that may not make noise.

jcb986 · 07-09-2010, 04:25 AM

I agree, check the motor mount first, they usually go bad around 60k miles. Also, the joints on the CV could be bad...not cheap fix. Check with NAPA Parts and see if they carry rebuilts or a German Dismantler. Also, rear axle bearings go bad and as for the pinion, you have a TIP and this is a very remote problem. If you can not isolate the problem, take it to an Indy and have them trouble shoot the problem and give you a price...then decided which way to go.

tylka · 07-09-2010, 07:08 PM

Thank you for the suggestions. I will check the motor mount this weekend and then go from there. I believe the pinion bearing would be the worst case. Axle or motor mount would not be too bad to replace. Thanks again.

tylka · 07-31-2010, 04:59 PM

Took me long enough, but I fianlly was able to take motor mount out of the Boxster and it was in need of replacement. The metal sleve in the mount was actually shifting to one side. No noises now and the car can now be driven like it was meant to be driven through the curves of the road. Thanks for the help.