TKO 600 Grinding.

[jhv48]

Went to the shop yesterday morning and examined the pieces.

Clutch is fine, throwout bearing is not.

The clutch fork (maybe due to the misaligned slave push rod) was off the fulcrum and applying a side load as well to the throwout bearing, possibly resulting in only partial release of the disc.

So, the pilot bushing may not have been the culprit after all. Might have been a series of events leading to a slightly dragging clutch disc. Every time we replaced the pilot bushing, we replaced the t/o bearing too just for safety sake.

Putting it back together today with a new slave bracket so the rod is pushing straight. New pilot bearing and a new t/o bearing.

Will test and report in a few days.

[Gaz64]

Originally Posted by jhv48

Went to the shop yesterday morning and examined the pieces.

Clutch is fine, throwout bearing is not.

The clutch fork (maybe due to the misaligned slave push rod) was off the fulcrum and applying a side load as well to the throwout bearing, possibly resulting in only partial release of the disc.

So, the pilot bushing may not have been the culprit after all. Might have been a series of events leading to a slightly dragging clutch disc. Every time we replaced the pilot bushing, we replaced the t/o bearing too just for safety sake.

Putting it back together today with a new slave bracket so the rod is pushing straight. New pilot bearing and a new t/o bearing.

Will test and report in a few days.

So it now appears the culprit all along was the relationship of the slave cylinder pushrod.

All clutch mechanisms push or pull on the throwout fork parallel to the input shaft.
If the push or pull occurs at an angle, it no doubt tries to twist the fork and apply uneven load to the throwout bearing.
If the bearing carrier has a little more than acceptable clearance on the bearing snout, it will not be parallel or concentric with the pressure plate fingers.
Uneven release results in a dragging clutch and difficult shifting, especially from rest.

[eschaider]

I haven't visited this thread in a while but I feel the pain you guys are going through. Consider this for a moment:

Whie it is possible that one or even two of you may have had a faulty throwout bushing/bearing installation, it is highly improbable that all of you or your installers can not master the installation of a throwout bearing.

The drag of an improperly installed or worse failed throwout bearing or an improperly adjusted clutch can overwhelm the synchronizers and produce the problem you are experiencing. The problem can also be produced by synchronizers that are barely up to the job of synchronizing the gear sets.

The problem is the latter not the former. The synchros in the TKOs are brass rings like we used to see on T-10s, Toploaders, and A-833 Chrysler 4 speeds. With the new lubricants, and metal finishing on the the synchronizer gear cones the plain old brass rings can't do the job anymore.

If you look at a T-56 they went from paper assisted dual friction surfaces to triple cone versions of the synchro to get improved shift quality. Tremec knows the problem there just hasn't been any fix available or desire to provide a fix - until now.

If you go to Liberty Gears they have an improved synchronizer available with a carbon fiber friction surface. They also have a retrofit to correct the 2-3 shifting problem. The synchros were about $50 each when I last checked and the shift fix was comparably cheap. Give it a try you'll like it.

Ed