Drivetrain 1989 T5 Keeps Breaking Throwout Bearings

Volvord302

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Sep 12, 2017
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Last winter I rebuilt my t5. In addition to the transmission i replaced the clutch with a luk and had the flywheel resurfaced. I also replaced the bearing retainer with a steel one and did the input shaft. Before the rebuild the clutch was fine, if a little stiff.

However since the rebuild i have been eating through throwout bearings. One luk, one cheap oreilly bearing, and now I'm on a timken bearing which is starting to make quite a bit of noise. When the first two bearings broke it was at the collar. At the last trans r/r i decided to replace the ball stud and fork which were quite worn.

Now the thing i have realized is the t/o bearing doesn't even contact the diaphragm springs until about halfway through the fork travel. In fact it is so far up the clutch doesn't disengage until the tob is partway past the bearing retainer.

I believe that is why i broke the first two bearings. The question is why is this happening? Could it be a combination of factors? And what can i do to remedy the situation?

Auxiliary info: i took a look at the luk compared to the original clutch (ford racing i believe) and it was a good 1/4 inch shorter than the ford clutch.
 
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Last winter I rebuilt my t5. In addition to the transmission i replaced the clutch with a luk and had the flywheel resurfaced. I also replaced the bearing retainer with a steel one and did the input shaft. Before the rebuild the clutch was fine, if a little stiff.

However since the rebuild i have been eating through throwout bearings. One luk, one cheap oreilly bearing, and now I'm on a timken bearing which is starting to make quite a bit of noise. When the first two bearings broke it was at the collar. At the last trans r/r i decided to replace the ball stud and fork which were quite worn.

Now the thing i have realized is the t/o bearing doesn't even contact the diaphragm springs until about halfway through the fork travel. In fact it is so far up the clutch doesn't disengage until the tob is partway past the bearing retainer.

I believe that is why i broke the first two bearings. The question is why is this happening? Could it be a combination of factors? And what can i do to remedy the situation?

Auxiliary info: i took a look at the luk compared to the original clutch (ford racing i believe) and it was a good 1/4 inch shorter than the ford clutch.


Sorry that I didn't see this thread earlier. I'll kick this off and hopefully some others will find it as well like, @Mustang5L5

I want to begin with your TOB engagement (had to make sure I was in a Fox forum, hehe). On a Fox, the TOB should almost always be in contact with the surface of the clutch springs. If it's not, it out of adjustment. A firewall adjuster and quadrant can help with this. Maximum Motorsport, Steeda, UPR, or my personal favorite is the Fiore Micro-Click (Google this as it's name has since changed).

Replace your clutch fork. Even if it's brand spanking new and still has the "Made in China" sticker still on it, replace it with a Ford factory piece. When you order the new clutch fork, order a Ford TOB as well. LIGHTLY coat the steel bearing retainer with high speed/heat grease. Just rub it in and wipe off the excess with a paper towel. You should barely be able to see it.

Replace the flywheel with a forged steel one. Start fresh, is what I'm saying.

If I missed anything, the guys will fill in.
 
This may help...


Help for those who have replaced the clutch assembly and are still having problems with adjustment:
The next step doesn't make much sense it you already have the transmission installed, but just for sake of discussion, here it is:
The throwout bearing sits in the clutch fork arm with the wave springs pressing on the rear flange of the throwout bearing.

?temp_hash=3b781a008f68f70d0bde9d6310e08fdb.gif
 
Sorry that I didn't see this thread earlier. I'll kick this off and hopefully some others will find it as well like, @Mustang5L5

I want to begin with your TOB engagement (had to make sure I was in a Fox forum, hehe). On a Fox, the TOB should almost always be in contact with the surface of the clutch springs. If it's not, it out of adjustment. A firewall adjuster and quadrant can help with this. Maximum Motorsport, Steeda, UPR, or my personal favorite is the Fiore Micro-Click (Google this as it's name has since changed).

Replace your clutch fork. Even if it's brand spanking new and still has the "Made in China" sticker still on it, replace it with a Ford factory piece. When you order the new clutch fork, order a Ford TOB as well. LIGHTLY coat the steel bearing retainer with high speed/heat grease. Just rub it in and wipe off the excess with a paper towel. You should barely be able to see it.

Replace the flywheel with a forged steel one. Start fresh, is what I'm saying.

If I missed anything, the guys will fill in.
Thank you for your response. The TOB being in constant contact with the springs isn't an issue as it's a hydraulic setup. The issue lies with how far along in the travel of the fork that the TOB makes contact with the springs.

Your other points are well taken. New forged flywheel, ford TOB, ford fork, and i figure a ford clutch while I'm at it. Do you have any other suggestions on a flywheel or a clutch brand? Motor is a stock HO with no real plans to wake it up yet.
Thanks again, pretty much confirms what I had intended to do.

Just as an aside, what do you figure would cause the contact point on the springs to be so far up? I had the flywheel shaved once not sure if it was done before.
 
This may help...


Help for those who have replaced the clutch assembly and are still having problems with adjustment:
The next step doesn't make much sense it you already have the transmission installed, but just for sake of discussion, here it is:
The throwout bearing sits in the clutch fork arm with the wave springs pressing on the rear flange of the throwout bearing.

?temp_hash=3b781a008f68f70d0bde9d6310e08fdb.gif
Thank you. I've had the trans out enough times that i got this down pat hahaha.
 
Yes i did.
Post a picture or tell us where the throwout bearing is breaking. We may be able to give you some additional help.

Is this a hydraulic or cable operated clutch? If hydraulic, does it still use the stock clutch fork? Is the input shaft housing steel or aluminum? The aluminum input shaft housings have a tendency to score and bind.
 
Post a picture or tell us where the throwout bearing is breaking. We may be able to give you some additional help.

Is this a hydraulic or cable operated clutch? If hydraulic, does it still use the stock clutch fork? Is the input shaft housing steel or aluminum? The aluminum input shaft housings have a tendency to score and bind.


Unfortunately i threw away the ones that broke but i have the original which was fine. Anyhow here is what happened.
The first picture has a red line where separation occured. It's on the collar where it meets the back of the bearing.

The second picture shows further damage to the collar. There was a deep groove on the nub of the collar that is supposed to keep it from spinning in the fork and a crack lengthwise on the collar. Obviously it somehow bound and spun the entire bearing and busted it.
Apologies if formatting is funny I'm on mobile.
 

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