veleno

'90 S2 cab

So if I run the car up to 4k rpm and above (in any gear), I get this vibration I can feel in the steering wheel, shift ****, seat bottom, and pedals. It's like the trans is getting mad at me! Anything lower than 4k rpm and it's not present.

It shifts fine, no grinding or slipping.

Help!

kev951

Pretty much normal, the fact that she's a cab makes it feel worse. But I'd be willing to bet your passenger motor mount is shot.

veleno

I'll have to take a look at that. Is the mount up top or below? Got a picture? Should I be looking for cracked or missing rubber?

My other 944 cab does not have this vibration, which is why I thought it was weird that this other one does.

Black Sea RD

Since you have an S2 it could be a bad front bearing in your torque tube (TT).

The 944S2 and most 968 models have a split in their TTs from the front and down about a third of it's length, put there to help dampen the vibrations form the larger 3.0 liter 4 cylinder engine installed in them.

With time the split widens and allows the front bearing to move around which causes them to become damaged. It then no longer supports the front of the drive shaft. This unsupported section of the drive shaft vibrates excessively and you feel what you are describing.

You can check it by looking through the slit of the TT (usually covered by an aluminum foil tape) and find the front bearing. Then visually check it to see if it looks damaged.

Here is a picture taken through the slit of a damaged one. You can notice the inner bearing insert has moved out of the front bearing and it sits above the bearing on the drive shaft. The other pictures show what you find when you remove the drive shaft and bearings from the TT.

Good luck with your research.

veleno

I'll check that too, thanks for the tip.

mhr

the engine mount that usually fails is the one on the exhaust side (passenger side). There is supposed to be a heat shield protecting it from the heat of the exhaust but sometimes it is missing and even when present it wears allot faster than the drivers side.

You can look at it to see if it looks collapsed cracked or if there is liquid leaking out. Best way to check is to measure it as per clark's garage the height between bearing surfaces on an installed mount should not be less than 60 mm.

Motor mount is allot easier to fix then torque tube so lets hope that is the problem.

veleno

I'll have time this weekend to take a closer look. I was just in my other S2 today and even in neutral there's no vibration when I rev it up close to redline. I'll keep my fingers crossed it's an easy fix!

sweetskillsrk

+1 on the motor mount, for your sake though I'm hoping it's not....not looking forward to the day when mine need replacing.

veleno

Looking at Clark's garage shop manual it doesn't look like it'll be hard, but what do I know as I've never done it before!

mhr

motor mount change is not that hard at all. Just make sure you get the high quality ones or you will be doing it again soon.