pepidcoe

I am the recent new owner of a 1990 928 GT. An unusual clutch pedal feel resulted in a trip to a local dealer. They replaced the master, slave, and clutch (a sequential progression since the problem did not get better with the initial replacements). They now tell me that they had difficulty reassembling the clutch because the torque tube was too long. They felt that that was putting undue pressure on the clutch and caused the initial problem. Do torque tubes get longer when they fail. The old one only had 30,000 miles on it (along with the clutch)? Will a new torque tube fix the problem? Thanks. -- Pete

deliriousga

What was the initial problem with the clutch? What was the "unusual feel"?

How are your motor mounts? I'd imagine if they are flat the 2" difference can cause some trouble with the angles lining up. I've never heard of a "too long" torque tube, but who knows what could happen with POs. Without actually seeing the problem it's hard to tell.

I would say a new TT is a pretty expensive "maybe it will fix it". I hate to make it sound like they're idiots, but did they look down at the other end of the tube to see if it's installed correctly down there? There could be something loose creating space or someone could have put something in that doesn't belong (i.e. washers).

pepidcoe

The clutch pedal was only returning 1/2 way back after a shift (when the car was cold). Seemed like a hydrolic issue. Replacing (and properly bleeding) the master and slave did not resolve the problem. In fact it got worse. The mechanics noticed that the master adjustment rod was threaded all the way out on the old part, which lead to looking at the clutch... -- I hadn't considered the motor mounts and don't know if the other end of the torque tube was investigated. I did see the old pressure plate assembly and the finger springs where the throw-out bearing sits were bend in a direction opposite the replacement - a difference of about 1/4"(?) I assume they were seeing a lot of pressure. By the way, the clutch and TT were both replaced 30K miles ago. All work done by dealers. Aghhh... -- Thanks -- Pete

worf928

Welcome aboard Pete.

A dealer (Porsche I assume) replaced the master, slave, and clutch. OMG. I can only imagine the magnitude of the bill.

Can you tell us what parts of the clutch they replaced? Disc only?

Also, as John asked, what were the symptoms that lead you to seek the Dealer.

Do you have any indication that the torque tube in your car has been replaced?

On a 5-speed the clutch assembly does not couple directly to the torque tube shaft. There is an intermediate shaft (less than a foot long) that bolts to the torque tube. This shaft normally has about 1/2" of forward-aft freeplay through a guide sleeve around which the clutch assembly rotates - before it is bolted to the torque tube.

I can think of several reasons why it would appear that 'your torque tube is too long' none of which are actually a too-long tube. Tell us more and we'll narrow it down.

I seriously doubt that throwing more money at the dealer will solve this problem. I suspect that you've already paid the dealer more than $2000 to throw random parts at the car and not fix the problem. In parallel with this thread I would suggest that you find another shop that knows a 928 from a hole in the ground - because the dealer does not appear to know the difference. If you let us know the region in which you live I'm reasonably sure you can be steered in the right direction.

worf928

Remove 'appear' from my previous. This dealer is staffed with idiots. They screwed up one or both the clutch and the torque tube 30k miles ago. Find thee quickley another shop.

worf928

And this was after the first clutch replacement and the TT job. I suppose it could be hydraulic. I can think of several mechanical possibilities that would fit with the evidence.

After the 30k-miles-ago clutch job was the operation of the clutch as smooth as butter? Or did you notice any increased vibration or noise during normal operation and/or engaging/disengaging the clutch?

Also, do you have the list of parts that was replaced this time and 30k-miles-ago?

I would be good to know what they (claimed they) replaced to understand potential root failure modes.

With all due respect to John, I don't think the motor mounts are a culprit. I've done clutches on 928s with new mounts and with mounts as flat as pancakes. No difference.

Which is why I believe that there is a mechanical explanation.

Jim bailey - 928 International

What ? "the torque tube was too long. " pure BS ... Motor mounts have no effect what so ever since the engine upper bellhousing torque tube and transmission are all bolted together and STAY together when replacing the clutch. Very unfortunate that the guesses by the parts changers of what might have been wrong, were wrong. MY GUESS is when the clutch replacement was last done they used superseded release bearing parts BUT did not replace the clutch arm. The updated part is 928 116 832 09 you might check the records of the clutch work.

ErnestSw

You are being handed a line of pure bull****. The 928 clutch is very simple to work on and torque tubes don't "grow". The ONLY way the clutch won't go back in once it's been removed is if someone has done something really stupid.
Where are you?
You need to find an honest mechanic who knows what he's doing.
The most likely cause of your initial problem was in the shifting mechanism itself. Could be the throw out bearing, the pilot bearing, the input shaft, or the linkage.

docmirror

Get your car away from the dealer! (hope that doesn't get me banned, it is an opinion). Investigate, and diagnose, then replace. You have different parts put if from the first clutch install job. That's why the rod is out of adjsutment. The disk, PP, and flywheel is probably fine. I would look into the linkage, arm, pivot ball, and release bearing.

Doc 90GT

pepidcoe

Wow... lots of responses. To recap... 30K ago, I was not the owner. The previous owner replaced the following parts after complaining of a vibration at 5000 rpm.
928-102-111-02 BALL BEAR --> $21.59
928-116-145-03 CLUTCH BA --> $13.07
928-116-911-02 CLUTCH RE --> $1140.30
928-113-426-41 RUBBER OI --> $26.14
928-421-012-26 CENTRAL D --> $1641.78

I saw the old clutch. There was only minimal wear. The big difference was the pressure plate assembly (the finger springs I talked about earlier). -- The dealer has gotten the clutch assembly back together, but said they had to put in non-spec bolts or spacer. They took it for a short drive and say the cluth feels great, but insist that there is still something wrong further back in the drive train. -- I am in Richmond, VA. Anybody know a GOOD 928 mechanic?

Jim bailey - 928 International

OK the central drive tube was replaced with a new one $1,641 so the transmission was disconnected that time . It is possible that the drive shaft got pushed forward BUT if so the clamping bolt at the transmission would NOT have fit through the groove in the drive shaft. The clutch kit listed is 89-91 style but probably was delivered with the updated release bearing and required the different clutch arm and guide tube. I am still guessing mis-matched parts

deliriousga

Brilliant I say! Sorry, I don't know how the motor mounts affect the 928, but it ripped the transmission to heck and back in another car of mine when they were dead. Great info to have.

I'm with them as far as getting it away from the dealer before they do anything else and cost you mucho more dough for nothing. I did the clutch with no experience and it is very easy so those guys should know better.

deliriousga

The clutch arm cup bushing is the right one so the arm itself must be ok, right? There were no previous clutch arms that would fit that size cup were there? Just thinking outloud.

Why would they need to put in spacers if there is already too much pressure from the TT? It seems to me if they say the TT is too long, there's no room for spacers.

docmirror

Uh, they replaced the tube, and then the mechanic complains about something wrong further back in the drive train? What is he referring to, the transmission, rear bumper, license plate? Fly me out there, I need to do a pre-buy on an airplane near Richmond. Someone will find a helper near you, just hang on a bit.

Doc

Jim bailey - 928 International

Doc two different sets of factory technicians two different "repairs" and thousands of dollars ...