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HH
06-10-2011, 08:50
I changed the clutch Fork and Ball in my K3500 about 90,000 miles ago, and now it is acting like it is worn out again. I greased it about 4 times a year (about every 5000 - 6000 miles), or does it need more than that? Is there any better set up than the GM fork and ball pivot?

HH
06-12-2011, 06:46
Wasted the day changing parts, both the fork and ball look hardly worn, unless the fork is bent. Guess it is time to change the slave cylinder as I did the master last year.

HH
06-14-2011, 16:53
It has not been my week. Rusted line cracked when I tried to remove it from the slave cylinder. Got a new line today. Starting to think I need a new truck :(

trbankii
06-14-2011, 19:02
Rusted? I think mine is only plastic...

HH
06-16-2011, 06:10
It is plastic from the master to just behind the engine, then it becomes metal as it passes the exhaust manifold and down to the slave.

jggiedeman
06-27-2011, 22:54
Were you able to change the ball and fork with the tranny still in place? What were some of your symptoms that led to replacing them? Thanks,

Jerry

trbankii
06-28-2011, 11:42
Can't imagine how to do the replacement without removing the transmission as you have to open up the bellhousing to gain access to everything.

For mine, the symptoms were a very heavy clutch up until the point something went bang and then there was no pedal pressure. The pivot cracked right through the fork:

http://www.thedieselpageforums.com/tdpforum/attachment.php?attachmentid=753&d=1211914876

You can see the whole thing documented here (http://www.thedieselpageforums.com/tdpforum/showthread.php?t=31207).

HH
06-28-2011, 18:38
Had to remove the trans and bellhousing :(. Works great now!...After new slave cylinder and hydraulic line. Would have been easier to install the hydraulic line while the bellhousing was out too!

Symptoms were a hard clutch pedal and hard shifting into 1st and reverse, and occasionally between upshifts and downshifts.

jggiedeman
06-30-2011, 20:13
So you changed the clutch fork, ball stud, master/slave cylinder only? My father-in-law stated that his DMF just started shir=fting hard into 1st and reverse. He's concerned he might have to replace the DMF. This is a babied truck with only 60k miles. No hard driving or towing. Thanks,
Jerry

HH
07-01-2011, 04:54
I did the fork, pivot ball stud, throwout bearing, slave cylinder, and hydraulic line. Only did the line because it cracked while trying to change the slave.

Did he grease the ball and fork? 60k seems low for wear on ball and fork, but if it was not greased? Most people do not realize there is a zerk fitting hiding on the bell. If you have it apart for a clutch or flywheel change it would not hurt to change, not that expensive.

jggiedeman
08-13-2011, 17:42
Finally got around to helping my father-in-law with his clutch job. 93 C3500. Had to remove the turbo downpipe to dip the engine far enough back to remove the tranny. First install - didn't check the tranny for proper shifting. Old pro by now on removing this. Had a neighbor drain and inspect the top cover. He didn't line up the forks and one of the plastic fork tabs wound up down below. He went home early and we proceeded to clean the tranny this time, found the piece, got it to shift properly.

Things found wrong - needle bearing pilot bearing (shot), throwout bearing (warbled all about). DMC seemed fine but installed single mass and clutch. Replaced clutch fork and ball stud. (don't lose the plastic shft device). Driveshaft coupling to tranny was missing one strap and the other strap was loose.

Injuries - did you know that the factory towing mirrors shred flesh and hair from your forehead? Didn't have much there anyway but sure left a Gorbachev spot to laugh about. Skinned nuckles and the usual gripping and groaning.

Saved him some $$ and they feed me nice.