Alternative to National Throw Out Bearing 614093

sierradmax

sierradmax

TJ Addict
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3 orders with two returns yielded the same Q.C. issue with the National Throw Out bearing. It's off-center. Similar buyers on Amazon claim recent purchases having same issues. I'm not sure if it warrants concern but IMO, the bearing should be centered... F' it and throw it in or should I order a Timken and see what that looks like?... They're probably all made in China anyways.

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I'll be replacing my clutch in the next couple of months and I'll be using the LuK TOB ... I ain't scared!!!
 
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I replaced my clutch about 15k miles ago when I rebuilt the engine, I went with a LUK kit, no complaints, but I was told whatever you do, do NOT go with a LUK throw out bearing, It has plastics components instead of all metal, there are "horror stories" of what has happened or so ive been told. Go with a timken TOB or Centerforce TOB. FWIW I run a timken and no complaints.
 
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Funny you posted this. My TOB went out while out here in AZ. I got a LUK kit and flywheel and the NATIONAL bearing. Yes China origin. Never looked for an eccentric condition.

Now it has an occasional “tick” or rattle noise when the pedal is free, slight depress of the pedal and it goes away.

Looks like there is a service bulletin from FCA that says the bearing doesn’t have enough preload and possibly the actuator rod from the slave cylinder might need replaced.

Meanwhile the LUK bearing is sitting here, I’ll sort it out when I get home.
 
Farmergreg said:
Funny you posted this. My TOB went out while out here in AZ. I got a LUK kit and flywheel and the NATIONAL bearing. Yes China origin. Never looked for an eccentric condition.

Now it has an occasional “tick” or rattle noise when the pedal is free, slight depress of the pedal and it goes away.

Looks like there is a service bulletin from FCA that says the bearing doesn’t have enough preload and possibly the actuator rod from the slave cylinder might need replaced.

Meanwhile the LUK bearing is sitting here, I’ll sort it out when I get home.
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I have the same noise symptom. I recently rebuilt my NSG with new bearings, seals, synchros and shift fork. while I was in there, I replaced the TOB and now I have the same ticking noise with the clutch out.
 
sierradmax said:
I have the same noise symptom. I recently rebuilt my NSG with new bearings, seals, synchros and shift fork. while I was in there, I replaced the TOB and now I have the same ticking noise with the clutch out.
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I had a shop down here do the work and felt pretty comfortable with the mechanic. I never inspected the national bearing nor the fork that moved it or the pivots.
Here is the LUK bearing:
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So correct me if I'm wrong...
A. If transmission is in neutral and clutch is not depressed (pedal out), the TOB is not spinning. Pilot is not spinning as the flywheel and transmission input shaft is spinning simultaneously... Therefore, input shaft bearing is spinning
B. Clutch depressed (pedal to floor), TOB is spinning, input shaft isn't while pilot bearing is.
C. Transmission is in gear and clutch is not depressed (pedal out), the TOB is not spinning. Pilot is not spinning as the flywheel and transmission input shaft is spinning simultaneously... Therefore, input shaft bearing is spinning..

The chirping noise is prevalent during scenarios A & C. Similarly to @Farmergreg , a slight press on the clutch and it goes away. I might try to remove the actuator and press on the clutch fork a bit to see if in fact there's not enough pressure when clutch is not depressed.
 
sierradmax said:
So correct me if I'm wrong...
A. If transmission is in neutral and clutch is not depressed (pedal out), the TOB is not spinning. Pilot is not spinning as the flywheel and transmission input shaft is spinning simultaneously... Therefore, input shaft bearing is spinning
B. Clutch depressed (pedal to floor), TOB is spinning, input shaft isn't while pilot bearing is.
C. Transmission is in gear and clutch is not depressed (pedal out), the TOB is not spinning. Pilot is not spinning as the flywheel and transmission input shaft is spinning simultaneously... Therefore, input shaft bearing is spinning..

The chirping noise is prevalent during scenarios A & C. Similarly to @Farmergreg , a slight press on the clutch and it goes away. I might try to remove the actuator and press on the clutch fork a bit to see if in fact there's not enough pressure when clutch is not depressed.
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In the service bulletin it mentioned the chirping specifically on 2006 TJ and early JK and talks about “preload” on the throw out bearing. Leading me to believe that it rides against the pressure plate.

Something might be different in the National bearing (Maybe the eccentricity you discovered) as there was never any noise for me prior to it’s demise.
 
I know the TOB rides along a stationary shaft that sleeves the input shaft. And that input has a bit of lateral play. With the TOB off the pressure plate and that little bit of play could create enough of an issue with an off-centric TOB...

I'm going to pull the actuator tonight and see if I can add a little pressure by hand.
 
I installed the LUK yesterday. Many reviews said they bought the National TOB to replace the LUK plastic. Others explained that the LUK TOB was designed to be more durable and many said they were having no problems with the LUK. I just went with the LUK. Did your steel one go bad? Yes, they go bad. Steel is not necessarily better than plastic.
 
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Any update on this. What you found? I installed a LUK clutch kit in my 2004 in April and it was quiet, then after about 2 weeks of daily driving I get a "chirping" when the clutch is out(released). If I put my foot on the clutch pedal(basically no pressure, just sitting on it) the noise gets a little louder and more constant, if I "push" the clutch pedal at all the noise goes away. There is no noise with clutch pedal depressed.
 
gasiorv said:
Any update on this. What you found? I installed a LUK clutch kit in my 2004 in April and it was quiet, then after about 2 weeks of daily driving I get a "chirping" when the clutch is out(released). If I put my foot on the clutch pedal(basically no pressure, just sitting on it) the noise gets a little louder and more constant, if I "push" the clutch pedal at all the noise goes away. There is no noise with clutch pedal depressed.
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Roughly 2 years with LUK plastic fantastic everyone is shitting on, no issues.
Every bearing has a chance to fail prematurely.
If LUK was disintegrating apart as much as people shit on it, SPECIFICALLY DUE TO ITS PLASTIC DESIGN. car industry would hear no end of it.

As far as ticking/chirping noise, watch this video:
I had that noise since the day i have purchased my Jeep. Replacing TOB has only postponed it for 2 month, and then it came back again. Then it disappeared just as magically as it appeared. Hot weather does have some sort of effect on it, during winter i don't hear a peep from it.

What exactly is causing your chirping could be one of the few things, anyone who points a finger at a specific issue without taking a trany out, should have their finger chopped off.

 
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