clutch not disengaging

[Tom Welsch]

All of the sudden my clutch will not fully disengage. Its not constant but when it acts up you can push the pedal to the floor the truck would still move. You can tell when it will act up as the clutch feels different. Im thinking its the hydraulics and am prepared to put a whole new south bend hydraulic system in. I just want to make sure its the hydraulics before i do that.

 

[fest3er]

Could be the throwout bearing is failing....

 

[chazj]

Mine was the hydraulics at 230,000 miles.
All the rest checked out ok.

 

[petersonj]

Mine was the pilot shaft bearing at 297,000 miles and I should not have waited that long to do a clutch job. When the pilot bearing failed with symptoms similar to yours, it damaged the transmission input shaft pilot bearing surface.

I still have the original hydraulics now at 340,000 miles. Your problem could be any of the above mentioned items. Are you on the original clutch? Do you have high mileage on the clutch. If the answer is yes to either of these questions, I would just do a complete clutch job.

- John

 

[Tom Welsch]

Petersonj my truck has about 240,000 km on the stock clutch. Thats about 150,000 miles for you south of the border fellas.

 

[KATOOM]

If repeatedly pushing down the clutch pedal to pump up potential leaking clutch hydraulics doesnt help release the clutch then its likely the pilot bearing or there's a problem with the clutch disc or pressure plate.

 

[Tom Welsch]

Thanks katoom. When it wont fully disengage i can let the clutch out fully and on the second attempt it feels and works as it should.

 

[KATOOM]

Check for any residual hydraulic fluid leakage of the master cylinder down under the dash and in the engine bay on the firewall. Also check the slave area on the bell housing and pull it out to see if there's any obvious signs of leaking. Just make sure you dont press the clutch pedal while the slave is out otherwise you'll shove the rod out.

If you do discover that either the slave of master is leaking then replacing them with parts store units is hard because they generally come separate and you have to install them and bleed them which poses a problem because due to the hydraulic line routing its impossible to bleed the hydraulics while on the truck. Which means they must be bench bled prior to installing and then you're trying to fish that hard metal line during installation.

My choice is the Southbend hydraulics. Its a factory unit which they have custom machined to fit a larger cylinder piston and then connect the master/slave together with flexible stainless steel braided line. It comes pre-bled and ready to install and the route of the SS line is short enough that if there's any air in the system then it will self bleed.
This setup is required for some of their aftermarket clutch kits but they're beneficial for any clutch since the hydraulics have more leverage due to the larger piston. More money, yes...but better than farting around with parts store garbage.

 

[gtwitch]

On my 99 2500, at about 100k miles, I also had the pilot bearing grind itself up and was seizing the input shaft and it would occasionally let loose but as soon as I slid the trans back to look, the ground up rollers came out of the end of the crankshaft as mostly dust grindings. Cleaned up and put a NAPA (china chincy) complete clutch kit with new pilot bearing and all was good for about 11 months (NAPA store here in Laramie WY would not cover it) so then I did it all over again with South Bend and I am still driving as a work truck and daily driver at 240K miles.
gtwitch in wyoming

 

[dblake]

They found my input shaft bad when doing my clutch. It got pretty expensive quick.