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Discussion Starter #1
I had searched for this question - how do I know if the clutch fork is actually bent or not?

I left my PSD sitting for past two months, believing that the problem was Sync rings inside Z5, were worn out.

My friend came to check other car and noticed that my truck was sitting for long time. I explained the problem, that stick won't shift from any gear while I was driving. Have to turn the engine off in order to change the engine, so I was stuck on 2nd gear to drive around a bit, just on the block, nothing farther. My friend suspected that it was clutch system, not the tranny.

What happened was that I checked under truck on the slave cylinder as he said that it is either that or the clutch fork. We played with it for a bit. I put slim (just a piece of metal with hole in middle, allowing the rod from slave cylinder to seat in there) between clutch fork and slave cylinder rod. Turned out that he was right. I am able to drive around and shifting. The reason why he suspected that was that he noticed that clutch pedal went all the way to the firewall and told me that it was not supposed to do that.

So big question is which one is at fault - slave cylinder or clutch fork?

After reading several posts, throw out bearing could be source of this problem?
 

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The OBS trucks didn't have the same problems with the clutch release lever (fork) that the SuperDuties did. It could still be a problem, but I would look at the condition of the Clutch Master Cylinder Rod eyelet, bushing, and linkage pin first as one (or all) are the usual culprits for this condition. If those check out OK, look at the brake/clutch pedal box mainshaft bushings. Also check the slave for any leaks and make sure that the slave rod travel is at least 11mm. Cheers!
 

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Discussion Starter #3
Got chance to check the movement. I measured the travel - 15/32" and it was roughly close to 12 mm. Meaning that clutch pedal/slave cylinder is fine?

I remmy the culprit about plastic thing on the rod eyelet. Replaced it once and it broke again later on. Right now, I put thin sheetmetal and wrapped it on the rod that goes through the eyelet and put tight plastic on the rod to hold the eyelet back in place. It works fine.

Haven't check mainshaft bushings yet. Will take a look at them closely.
 

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I've always heard that the travel should be at least 1/2"; in any event, you're right on the margin. Do you feel play in the pedal, like no resistance for the first bit of pedal travel?

Your adaptation for the eyelet is probably better than the original plastic [email protected], but there are two more permanent options:
* If the eyelet isn't damaged ("egged out" or ovalized), you can make a bushing out of a short piece of brass tubing, 1/2"OD x 7/16"ID. Assemble, and then put a 7/16" drill stop collar on the end of the pin that goes through the eyelet to secure.
* If the eyelet IS ovalized, your best bet is to cut it off and replace with a Heim joint. There's a kit on eBay, or you can buy the parts yourself at McMaster-Carr or Fastenal or wherever for a lot less.

The physical position of the arm that holds that pin could be a factor, too. You can sometimes remove it and "re-clock it" in a position such that it pushes more on the pushrod as you push the pedal through its movement.

Bent fork is not out of the realm of possibility. IIRC, Patrick is right, there was no TSB on the OBS fork, but I believe they did come out with a more robust update to it.
 

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Discussion Starter #5 (Edited)
For the play on the pedal, I felt beginning of pressure, after about 2 inch travel from starting point. Clearly, about 2 inch of play there. Is that too much?

Checked brake/clutch pedal box mainshaft bushings, can see that they are not "static" but little movement like 1/8-1/4" and I was surprised to see that movement. It is not really at bushing but on the firewall with vertical metal "stud" and the mainshaft on right side (where eyelet is at), it moved a bit upward toward to the dashboard.
 

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Yeah, that's too much free play.

Another pedal box test - very lightly set your right foot on the brake pedal (don't actually move it at all), then work the clutch pedal with your left foot. If you feel any "feedback" in your right foot from the clutch pedal movement, then there's slop in the pedal. First thing to try is the bushings, but similar to the eyelet, if the holes in the pedal box "frame" are enlarged, it may be too late.
 

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Discussion Starter #7
My son heard loud "EEEEE" noise from the bottom of the truck, pointing to the transmission. I pressed the clutch pedal and it made that noise then released the clutch pedal and the transmission is in neutral. The noise quieted down. Seem that throw-away bearing was worn out, seem this is the answer to the problem?

I could not hear it :icon_rolleyes: because I am deaf PSD owner. :yesnod:
 
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