Transmission question, 901 related Options

[MartyYeoman]

I have started to notice noises that I attribute to excesive differential clearance.
When shifting up I can generate a "clunk" type sound. Also while driving I can generate the same thing by feathering the throttle. I can eliminate the noise by being excessivly smooth on acceleration. I seem to be able to duplicate the sound by raising the rear wheels off the ground and rotating the rear tire.

My questions are: How is the pinnion/ring gear clearance set? Can it be adjusted with the dirve train still in the car? How long can I let this go?

[r_towle]

in this order

Front and rear engine mounts.
If newer type with a side shifter you need to make sure the front mounts on the outer part of the bar, where the bar attaches to the body are nice and tight.
The front inner ones are rubber with a bolt glued inside and are not repairable, just replacable.
I am guessing that might be the issue.
Aslo look at the rear mounts from tranny to body, but these are pretty solid
The clunk could be from the engine rising up on one side due to the amazing amount ot torque that these little monsters produce...seriously it will make that sound.

Easiest check, have someone do it while you watch from outside, and look into the engine bay...if the motor moves when the engage the clutch...its the mounts.

CV joints will click while going forward or backwards just a little bit, again easier to hear from outside the car.

Rich