Clutch replacement at 297,000 miles

[Tractorman]

 

I thought I would share my experience with the clutch replacement job on my truck.

I just did a clutch replacement on my truck after a good service life of 297,000 miles.  However, in hindsight, I know now that I should have replaced the clutch much sooner, perhaps at around 225,000 or 250,000 miles.   The primary failure was the pilot bearing which I had noticed recently because at times there was difficulty getting the transmission into gear with the engine running.  Eventually, the needle bearings were spit out and the shifting problem went away.  However, the failed pilot bearing damaged the bearing surface area on the input shaft to the transmission. 

I replaced the clutch disc, pressure plate, T/O bearing, pilot bearing, and flywheel.  I decided to go with Napa because the clutch and pressure plate were manufactured by Luk, as were original clutch parts.

I elected not to replace the damaged transmission input shaft at this time because I think that even with the pilot bearing surface damage, I can still get a reasonable service life before doing another clutch job.  At that point the transmission may need other parts as well and all the work could be done at the same time.

The photos show some of my observations.  The friction surface of the pressure plate is not shown, but it looked the same as the friction surface of the flywheel.  Also, the heat marks on the flywheel and pressure plate were caused by one event in which I was slipping the clutch repeatedly under a light load to diagnose a steering problem.  I could smell hot friction material during this testing.   Not one of my brightest moments.

 

- John

 

 

 

 

Edited August 8, 2018 by Tractorman

[Dieselfuture]

Any pictures of input shaft

[Tractorman]

37 minutes ago, Dieselfuture said:

Any pictures of input shaft

 

No, and of course it would have been the most important picture.  The needle bearing chewed away a few thousands of an inch of pilot shaft material all the way around the bearing area precisely the length of a needle bearing.  Because of the missing material, the new needle bearing will not support the pilot shaft as well as before when the clutch is disengaged.

 

- John

[Dieselfuture]

Wonder if a sleeve of some sort can be put on

[Tractorman]

8 minutes ago, Dieselfuture said:

Wonder if a sleeve of some sort can be put on

 

Since the very tip of the pilot shaft did not receive any damage, a sleeve would not fit over it.  I think that in order for a sleeve to work, some machining would have to be done to reduce the diameter of the whole bearing area on the pilot shaft.

 

- John

[BBHD]

At least your clutch did not self destruct as mine did when I lost the pilot bearing. Fortunately I had no adverse wear on the input shaft.