08-23-2005, 10:33 PM
I just wanted to post some consolidated info on the pinion bearing problem that our cars have from time to time for the archives...
(Note: Much of this compiled from random sources, but heavily from
http://members.rennlist.org/martin)
What is a pinion bearing: the 968 has a transaxsle i.e. the gearbox, final drive and differential all in one unit. The gearbox output shaft has at its end a pinion gear driving the crown wheel. This shaft has a big 'pinion' bearing on one end and a smaller one at the other end. A pre-load is applied by way of shims and a nut at the smaller end of the shaft.
Who gets this problem? It is a manufacturing defect in some cars. Some people are guessing from 2% to 10% of our cars. It seems to happen anywhere from 0 to 80K miles, with very few instances over 90K miles.
How do you know you have the problem? The main indicator seems to be a noise similar to the whine of a jet engine. Common tests for the problem include running the car up to about 80mph on a smooth road to avoid road noise, coast, and listening for the jet engine noise coming from the rear of the car.
How much does it cost to fix? Anywhere from $1500 to $3000 it seems depending on where you get it done. It is a complicated procedure to fix so make sure the shop has good knowledge of the 968.
(Note: Much of this compiled from random sources, but heavily from
http://members.rennlist.org/martin)
What is a pinion bearing: the 968 has a transaxsle i.e. the gearbox, final drive and differential all in one unit. The gearbox output shaft has at its end a pinion gear driving the crown wheel. This shaft has a big 'pinion' bearing on one end and a smaller one at the other end. A pre-load is applied by way of shims and a nut at the smaller end of the shaft.
Who gets this problem? It is a manufacturing defect in some cars. Some people are guessing from 2% to 10% of our cars. It seems to happen anywhere from 0 to 80K miles, with very few instances over 90K miles.
How do you know you have the problem? The main indicator seems to be a noise similar to the whine of a jet engine. Common tests for the problem include running the car up to about 80mph on a smooth road to avoid road noise, coast, and listening for the jet engine noise coming from the rear of the car.
How much does it cost to fix? Anywhere from $1500 to $3000 it seems depending on where you get it done. It is a complicated procedure to fix so make sure the shop has good knowledge of the 968.

