Grinding Noise from Under Car
> My 82 928 is making a grinding noise from under
> the car when it is in neutral and the
> clutch out. When I depress the clutch the noise
> Is it a bearing of some sort that is about the
> break ??
> Karl - 82 928
If you depress the clutch with the car in neutral and get the noise, but it goes away with the car in gear and clutch depressed, it indicates your torque tube bearings are toast.
Another possible cause of chattering is a disintegrated bush at the clutch release arm. This allows the arm to rattle loudly when there is no pressure applied to hold it against the ball socket, but then quiet right down when you depress the pedal and firmly lock it against the ball.
Hope this helps narrow the problem.
86.5 Indischrot 5-speed
I suggest you get the car somewhere where you can raise it and listen to the noise from underneath. If you read the instructions for lifting and supporting the car level from a week or two ago, follow those instructions.
Once underneath, you'll be able to isolate the area that the noise is coming from. This might be a throwout bearing, most probably the torque tube, might be in the front of the gearbox. Once the noise is localized this way, you may want to isolate it using a stethoscope. Be aware that the exhaust will get hot and it will burn you if you roll into it, so get the car up high enough to avoid unintentional contact with the pipes.
While you are under there, the oil levels in the gearbox and the differential need to be verified. Over 25k miles since the last fluid change there? Time to get new oil in there anyway. If the noise is genuinely coming from the gearbox, the forst step undoubtedly will be an oil change, and an upgrade to Redline or Swepco gear lube.
The most popular source of the noise you describe is probably the torque tube. Rebuilt tubes come locally (to me) from Mark Anderson at 928 International in Anaheim. www.928int.com will guide you to him. DEVEK and 928 Specialists undoubtedly have them available too, at www.devek.net and www.928gt.com, respectively. I've never changed one (knock on wood...) but understand that it's not a huge job. Looks to me like the gearbox gets unbolted and moved back some to free the shaft up. You'll want to read the instructions in the manual, or get the how-to info from your tube supplier.
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