Porsche Enthusiasts Club Forum

Hi all
After about 60 motorway miles this weekend there was a vibration and low pitched rumble from my transmission. I slowed down a little, put the gearstick into neutral, then back into fifth gear and carefully lifted my foot off the clutch. The vibration and rumbling disappeared for a few miles then returned.
I don’t seem to have the problem at low engine revs, or when I haven’t done many miles.
Could this be torque tube bearings?
Thanks
Neil

I don't think its torque tube bearings. To check for torque tube noise get the car nice and hot with a good run.Then stop the car some where quiet. If you can hear a shhhhhhhh sort of noise, continuous in tone, press the clutch down. If the shhhhhh noise stops and returns when you bring the clutch pedal back up that is torque tube bearings.

your vibration and low tone could be wheel bearings - long motorway run warms everything up and everything expands and gets a little looser. Try listening for it when you go round corners. Also do you get a vibration in the steering wheel - if so probably the front wheel bearings

Or:CV joints - have you checked the rubber boots for splits etc?

Or: Could be gearbox noise more apparent when the gearbox oil is nice and hot but that doesn't usually give a vibration

There is a vibration in the steering wheel when I get this problem, I'll check to see if there is any play or noise on the front wheels



I replaced the rear wheel bearings a couple of thousand miles ago and checked the CV joints at the time, they seemed to be OK.

I'll take it for a long run at the weekend and try listening for the noise as I depress and release the clutch, I'm hoping it will be the front wheel bearings!

Thanks for taking the time to reply to my question, it's much appreaciated
Neil

The engine mounts could be on the way out, they bolt to the front cross member that the control arms attach to. At higher rpm is when they are most likely to give you a vibration. It will also transmit through the transmission as well. The right-hand side is most likely to be the culprit to fail due to its proximity to the exhaust manifold.