mhuppertz

Having to daily my truck again (long story) and having trouble with clutch disengagement issues, especially once the truck is warm.
It has nothing to do with the hydraulics, replaced those three times.
Can't figure it out. If the pilot shaft bushing was failing I would think it would be worse when cold, but that might not be correct.

Thoughts? Experience with this?

maybe368

When my pilot bushing was failing, it became very hard to get it into reverse. I thought I was going to break the shifter a few times. I don't know for sure, but I would think that a failed pilot bearing may cause disengagement issues...Mark

edwinsmith

When I got my truck the pushrod clevis on the pedal was worn such that it was difficult to depress the pedal far enough to engage the starter lockout. I did a temporary fix to the clevis with a makeshift bushing. This would eventually have caused the clutch to not disengage fully I think but it never got that bad.

When I had my transmission swapped out I had trouble with the clutch not disengaging but it was temporary and worked itself out. I think it may have been air in the hydraulics.

I eventually swapped out the master, slave and the plastic line connecting them which fixed my bad clevis at the pedal. This made my pedal higher and made things much better.

Some have suggested a bad crankshaft thrust bearing will cause this because the crank and everything is forced forward away from the clutch fork/throw-out bearing.

Edwin

Angry Johnny

Need more info, is the pedal hard to push? Does it go all the way to the floor without much resistance? Does it have any free play in the pedal and how much if any? Does it slip at all under heavy load? Are you having trouble getting it into gear after a stop or while changing gears while driving? If so which gears? Does it make any noise when operating the pedal? If you start it in gear does the truck want to move?

Any and everything that doesn't seem normal and please be specific. Just saying it doesn't disengage when warm is pretty vague.

mhuppertz

Ok, here goes. The pressure feels normal, but yes it goes to the floor. This is mostly because I broke the bulkhead brackets that hold the clutch pedal and pushed out the firewall a bit. I did my best to repair with steel and welding, and it has worked fine that way, even though it is annoying.

It goes in and out of gear fine when it is cold, but as it warms up it gets harder and harder to get it in and out of gear, both at idle and when changing gears. The transmission is fine, and the clutch never slips.

I have to shut off the engine to get it back in gear waiting in line for food, etc.

Like I said initially, it isn't the hydraulics because this is my third set of sealed units.

Making it miserable to drive.

The only thing I can think if is the pilot bushing is galling, but that doesn't quite feel like the answer,

Thanks!

Mark

maybe368

Sounds like the pilot bushing, or bearing if you have converted it...Mark

Angry Johnny

Honestly in all my years I have never seen a pilot bushing or bearing do this. It would have to be galling to the input shaft to cause this. I'm not saying it can't happen but in 43 years I have never seen that on any vehicle. If the the master cylinder is getting it's full stroke, meaning the firewall and pedal assembly isn't flexing, and the slave cylinder isn't moving around you most likely have a pressure plate problem. You didn't say how much if any free play you have. I have also seen pieces of the disc fiber coming off and getting caught in between the disc and flywheel or pressure plate. The disc or the pressure plate could be warping causing it to drag and not release all the way. Either way it looks like it's time to pull the trans.

maybe368

In my 40 years of wrenching, I have seen shifting problems from a destroyed bushing once, on my rig, so it can happen. Either way the tranny comes out and I change out the pilot bearing every time the tranny comes out, which falls under the "while you're in there" rule...Mark

edwinsmith

I didn't touch my clutch or pilot bushing on my 55 Chevy because I had the trans out every other week fixing the synchros.

SORTIE

Mark, you're describing symptoms I had in my truck a few years ago. I replaced the Getrag with a re-built and installed a HD South Bend clutch, but fast forward and I'm having trouble getting it into reverse again. After 150 miles of towing 6,000# of boat, I find it hard to get it OUT of gear too.

I started a thread on this a few weeks ago since my mechanic tells me that my crankshaft has too much fore-and aft play in it. I decided to have the shaft serviced, rather than laying out the bucks for a re-built 6BT. Good luck, I'll be reading this thread with interest.