What't the worst that can happen with a bad throwout bearing?

glenn1179

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Oct 3, 2005
Location
wausau, wi
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I am normally a lurker and can find the information I need by searching on this site. (Thanks, by the way.) Here is one that I haven't found much information on though.

I just replaced the clutch, throwout bearing and pressure plate on my 1Z 96 Passat. I also changed the trans oil and axle seals while I was in there.

I now have a noise from the front of the transmission that sounds like my new throwout bearing is suspect. The hours of labor are too fresh in my mind to want to tear it apart again for just the bearing.

The noise goes away when the clutch is pressed to the floor and everything is working smooth now. But, what are some scenarios of what will happen if the bearing fails?
 

validius

Lacking in ZDDP
Joined
Oct 9, 2006
Location
Grand Rapids, Michigan
TDI
1997 GTI TDI
The bearing is only under load when the clutch pedal is pressed, not released. You could just be hearing clutch rattle, its common.

If the bearing were to seize or fly apart you could chew up your pressure plate or the lever that the slave cyl actuates that the bearings attaches to. There is always the risk of destroying your trans if a piece of metal gets wedged in the wrong place, breaking the housing however the most likely scenario is that you will be confronted with the inability to release the clutch.
 

glenn1179

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Oct 3, 2005
Location
wausau, wi
TDI
na
Just to make sure I have it straight... if the bearing is under load and it doesn't make noise, then it is likely ok.

What exactly is clutch rattle? Is it just my throw out bearing rattling on the guide some since there is no load on it?

I bet this is all because I didn't put the "brick" counter balance weight back on the car. ;)
 

Joe_Meehan

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Sep 3, 2005
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Ohio USA
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NB TDI, 2002.5, Silver
The most beautiful woman in the world asks you for a ride across county, and you can't shift gears.:D
 
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tdibeliever

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May 2, 2003
Location
Urbana, IL
TDI
None currently- just pieces
The rattle is the springs in the center of the clutch disc. You shock them enough and they shorten up. When they're smaller than the cavity they are supposed to occupy they rattle. When you put your foot to the floor the springs are under load and the rattle goes away.
 

glenn1179

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wausau, wi
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tdibeliever said:
The rattle is the springs in the center of the clutch disc. You shock them enough and they shorten up. When they're smaller than the cavity they are supposed to occupy they rattle. When you put your foot to the floor the springs are under load and the rattle goes away.
This was a brand new Sachs replacement clutch disk from a tdiclub approved parts dealer. Is the part defective? It made the noise from the instant I started the car after installation.

I drove it home after the clutch broke and I had to shut it off to stop and get into first gear, so if that pretty lady needed a ride, I would find a way to make it work. :eek: :)
 

Ookpic

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Jun 20, 2008
Location
London, ON - Port Huron, MI
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2002 Golf 2Dr 5spd
Did you put in a lightened flywheel?

Easy way to check if it is the "flywheel chatter" is when you are at a stop and put the car in neutral and release and engage the clutch pedal. If you hear the chatter when the clutch pedal is release and it goes away when you depress the clutch pedal then I believe this is normal with aftermarket Lightened SMF's.
 

ymz

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May 12, 2003
Location
Between Toronto & Montreal
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2003 Jetta TDI Wagon, 2003 Jetta TDI Wagon
Another cause of "chatter" is wear in the clutch fork pivot point... Not a bad idea to replace it when the transmission is out of the car...

Yuri.
 

VWWV

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Joined
Sep 9, 2003
Location
Florida and WV
TDI
passat 96, candy white
validius said:
rattling is normal with the clutch engaged (pedal not pressed). Dont worry about it.

Thanks Validius. My 96 B4 has had the rattle since almost new and I always thought it was the throwout bearing and I've been wondering if it was a time bomb? The rattle keeps me from letting the engine idle in neutral and I guess that's a good thing? Commonly, 3 or 4 pumps of the clutch pedal will quiet the rattle for those few times I want to idle in neutral. Thanks to the OP for this thread.
 

MicroVW

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Joined
Nov 8, 2004
Location
Glendora, CA
TDI
Jetta, 1998, White
Did you put the little metal keep that hold the fork on.The last time I did my clutch I forgot to put it back and would get a rattle when the clutch pedal was not pressed in.I had to do more work on the car and reinstalled in and a lot less rattle.
 

glenn1179

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Location
wausau, wi
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na
No, I didn't install a lightened flywheel. I removed mine, replaced the rear main on the engine, and cleaned up the flywheel with a Scotch Brite pad before reinstallation. I did not replace the clutch fork pivot, but I did remember the clip.

I have about 200 miles on the clutch now. The noise is more pronounced with the clutch pedal out and the car in neutral. It goes away when the clutch pedal is pressed in, but I also hear it when the car is in gear and the clutch pedal is out. I would describe the sound (at all times) as less of a rattle and more of a scratching or screaming, like when drilling into steel. It sounds so bad, my girlfriend wouldn't ride in it for a road trip and insisted we take her car instead. :eek:

I guess my plan is to continue to drive it. Either it will break and I will have a good reason to tear it apart again, or I will begin to accept the noise and learn to trust the car again.
 

Clayslayer

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May 16, 2009
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Rapid City
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2002 Jetta and a 1977 Ford F-150 with a 4BT Cummins
My '02 Jetta TDI makes the same noise. Drives me freaking nuts. I was told that it was a bad DMF so I replaced it with an SMF and the sound, if anything, is worse now.

Car drives just fine, sound goes away when I push in the clutch, but idling in neutral sounds like I'm rolling a ball bearing around in a metal coffee can. Oh well. The car was cheap, gets great mileage, and drives just fine so I'll drive it until the wheels fall off of it. Hopefully that'll be a long time from now.
 

vanagonjon

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Sep 22, 2007
Location
Pelham, MA
TDI
96 Passat Wagon
A while ago I noticed my car started making the same rattling noise; I just figured it was the TO bearing. My clutch fragged a few thousand miles ago and I replaced the clutch, flywheel, and TO bearing but the sound did not go away. I asked a transmission guy who is familiar with the 02A and he told me the noise is from the transmission.
 

RIP TDI

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TDI
'15 GSW SE 6MT...... '01 Golf GLS 5MT.... '96 Passat Variant....
vanagonjon said:
A while ago I noticed my car started making the same rattling noise; I just figured it was the TO bearing. My clutch fragged a few thousand miles ago and I replaced the clutch, flywheel, and TO bearing but the sound did not go away. I asked a transmission guy who is familiar with the 02A and he told me the noise is from the transmission.
If its a classic gear rattle in neutral, it probably has nothing to do with the transmission and everything to do with using a VR6 clutch kit.

A VR6 clutch kit will usually cause a gear rattle because the cushion springs in the VR6 disc allow 4-cyl. engine harmonics to be transmitted to the transaxle gears in neutral that the TDI/G60 disc springs filter out.

Sachs TDI clutch kits use the SAME pressure plate as the VR6 kits so there is no disadvantage to using it and a definite disadvantage to using the VR6 kit.
 

RIP TDI

Top Post Dawg
Joined
Feb 16, 2000
Location
Santa Barbara, CA
TDI
'15 GSW SE 6MT...... '01 Golf GLS 5MT.... '96 Passat Variant....
Clayslayer said:
My '02 Jetta TDI makes the same noise. Drives me freaking nuts. I was told that it was a bad DMF so I replaced it with an SMF and the sound, if anything, is worse now.
Which is exactly what you would expect. If gear rattle is unacceptable to you, a broken DMF should be replaced with an updated, redesigned DMF. That's the whole point of DMFs; to eliminate gear rattle. A SMF can be used for reliability's sake as long as you understand and accept the inevitable resulting induced gear rattle.
 

kustomart02

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Joined
Jan 5, 2006
Location
san jose
TDI
2005 TDI Jetta wagon
exactly the same thing with my 05.5 pd wagon. For about 30k miles. From my experience I was figuring a throw out bearing/unbalanced flywheel. This is my experience with Case farm tractors diesel and regular gas cars...not that clutches and trannies are that much different.

I was not sweating too hard on the clutch because that didn't make since. I was figuring some stupid dampener or something, but worried that if/when whatever comfort added part goes it could shread metal through the housing...

OK so mine is like this:

clutch pedal out (engaged): chatter
clutch engaging to point of release: ball bearing in coffee can sound
clutch pedal in (trans connected): silence
shifting fine all gears.

no slip no noise when working.

thanks, I think I'll wait until my secong timing belt then break the cases apart.
 
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