jdk1

I know it is impossible to diagnose a noise over the web, but some educated guesses would help. I have a '99 C4 and just noticed a new noise today. It occurs at speed and sounds something like a 'squeaky metal roller.' The noise disappears when the clutch is depressed. As soon as I begin to release the clutch (at the floor - a significant amount of travel from where it begins to grip) the noise starts again. Throwout bearing? Any guesses? I have had a transmission go bad before and it doesn’t sound like a pinion whine.

Thanks.

kilrgt

Yea sounds like a throwout bearing, while you in there you might as well do a clutch kit.Again its very hard to tell, but your describtion does sound like a throwout.

jdk1

Thank you very much for the reply. Is there any harm in driving it until it's ready for a clutch?

1999Porsche911

Not the symptoms of a bad throwout bearing. IF, and I say, IF, the noise is coming from the tranny area, it may be gear noise. See if you get noise when you are in neutral, engine running and clutch out. See if noise goes away when clutch is depressed. Throwout bearing will make noise as pedel is depressed.

Scouser

Sorry but that's sounds exactly how my gearbox problems started. As time goes by it will get louder and louder. In the end I had to replace it. I hope for your sake I am wrong.

The throwout bearing has more of a screetching sound.

jdk1

I just want to update this thread. The noise was confirmed by two mechanics as being the rear differential / transmission. I had an independent mechanic pull the transmission and ship it to Roger Brown at Powerhaus II. He couldn't have been any more knowledgeable, patient, honest and fair with his pricing. It was truly a pleasure working with somebody that wasn't just guessing at the problem. The transmission was in and out of his shop in just a few days.

Below is part of an e-mail he sent me explaining the problem after it was taken apart:

"Attached are some photos of your gearbox internals. The debris on the magnet is a dead giveaway that a major failure occurred. I now suspect the main input bearing failed causing 4th drive gear to collide with 3rd driven gear. In pic "3rd 4th a" take a close look at the gear on the left side and bottom. It's kinda hard to see but the top of the gear is now "tapered" from 4th cutting into it. When the clearance went away the bearing assembly under 3rd idler on the pinion shaft exploded, ruining the input shaft~more debris. The hardened thrust washer between 3rd and 6th also broke into several pieces. Second gear synchronization looks okay; better than expected. I also think 3rd/4th slider will be okay but I know the hub is wasted. I have not broken down the box all the way as of yet but have identified 99% of the parts that need replacing."

I will post a final update once the project is complete. Some pictures Roger sent me are below:

jdk1

The car is finally back together and on the road again - top down I might add. The transmission is as smooth as butter and the new clutch makes all the difference in the world.

Thanks again to Powerhaus II and Sunset in Oregon! Total cost for the clutch and transmission rebuild (including labor, parts, fluids, shipping, etc) was about $5,500. Interestingly enough, after all of the discussion on this board about gear lube Roger at Powerhaus recommended Redline 75W-90 for his rebuilt trans and suggested changing at 30K rather than the suggested 60K.

I appreciate all of the help from Rennlist!

Palting

Scary sequence of events. As I understand the thread, the car was running and shifting fine. The only problem was a "squeeky roller" noise that went away when the clutch was depressed. This was due to a "major failure"????????

jdk1

I should have updated the symptoms as well. The driveline noise was present throughout the sequence of events. The day after I made the first post 3rd gear began making a noise like a baseball card in bicycle spokes. There was no difference in 'feel', just a horrible noise and eventually movement in the shift handle.