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Nipntuck
06-02-2011, 14:53
Hi everyone,

I have a 2001 2500 Duramax with a 6 speed manual transmission. About 3 weeks ago the clutch went out (while towing a 3 horse trailer) at 95K miles ~apparently the slave cylinder developed a leak. So it now has a new clutch, pressure plate, slave/master cylinder, pilot bearing, and flywheel. Now the truck has a significant shudder/stagger when I shift from 4th to 5th gear when I am hauling, especially when going up hill. I am also running the engine RPM's higher than I used to to try to smooth the shift (was able to do the shift at 35-38 mph, now needs to be at least 40 mph and it feels too high). I've put 10-15k towing miles on this truck with the same trailer without these problems prior to the clutch issue.

I took truck and trailer (loaded with horses) to the dealer today and the mechanic rode with me and experienced the shudder and he doesn't think it has anything to do with the clutch, but wants to rotate the universal joint. He also thinks tires might be causing it.

Can anyone give me any thoughts on this? The timing is just to close for me not to think of clutch/transmission issue and it's a real PTA while driving. I'm not hard on clutches. When I sold my Datsun 280Z it had 230k miles on the original clutch and while this is the first "heavy duty" transmission/clutch, I've driven a stick my whole life.

Thanks for any ideas!

More Power
06-03-2011, 12:19
An updated flywheel was released in July 2004 that was designed to increase life, improve friction control and reduce transmission input shaft wear.

According to ZF (manufacturer of the transmission), for a clutch chatter or shudder problem, you should consider the following:

· Engine/transmission mount loose/damaged.
· Bolts retaining clutch pressure plate to flywheel loose.
· Clutch pressure plate worn/damaged.
· Clutch disc facing oil coated.
· Clutch disc facing hardened/damaged.
· Clutch disc runout excessive.
· Flywheel surface glazed/damaged.
· Flywheel runout excessive.
· Transmission input shaft eccentric/not perpendicular.

Jim

Nipntuck
06-03-2011, 19:38
Thanks for the information! It should have a new clutch plate and the new flywheel was the newest GM flywheel. Time to do more research.