i have a94 f350 with a zf grinds going into reverse only? all other gears fine any clues? thanks guys

 

Shee's getting ready for a rebuild.

 

Is the clutch dragging any? Even if its not grinding, do you have to force it into first?
The pilot bearing was shot in my truck, it would always grind going into reverse. I got into the habit of shifting into 4th before reverse and it would usually go without the grind. The pilot bearing was causing the input shaft to drag so it wouldn't shift right. So it might not be the tranny just yet.

 

Here is the ZF trouble shooting guide....

ZF Friedrichshafen AG / Troubleshooting Guide



I saved this post a while back.........

Re: ZF-5 wont go into gear by FIDO

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I had the same problem with my 5-spd.
If you're sure there is no air in the system then you need to get under the dash and look for where the slop is in the linkage.
The first thing ZF recommends for poor shifting checking the clutch slave cylinder and linkage for proper operation.

The bushings in the pedal linkage are a known problem area.
Ford makes a replace bushing kit for whole brake and clutch pedal assembly, the part #F3TZ-2C342-A costs about $40.
The bad part is you have tear the whole bottom of the dash off, both master cylinders, & disconnect the steering column to get it out.

The master cylinder linkage is also prone to wear out. This is what I had been fighting with on mine. There was almost 3/8" of combined movement between the pin and the master cylinder link eye. Previously, I tried a brass bushing from ACE hardware, but it wore out after a few months.

I needed to replace the pivot pin and the master cylinder link. You get a new link with a replacement master cylinder, but no pin.

I bought a rod end and shoulder bolt from McMaster-Carr to be my replacement pin and link end.

Here's my parts list from McMaster:

60745K441 High-Strength Ptfe-Lined Ball Joint Rod End, 3/8"-24 Rh Female Shank, 9550 Pound Load Capacity - $14

91264A580 Alloy Steel Self-Locking Standard Shldr Screw, 3/8" Shldr DIA,5/8"L Shldr, 5/16"-18 Thrd,w/Pell - $2

2573A33 Hex Rethreading Die, Right Hand, 3/8"-24 Nf, 25/32" Width Across Flats - $15

NO Tax - Shipping was $5.

I cut the end off of my master cylinder link with a grinder right behind the link eye and treaded it with the Hex die. It was easier to use this die inside a socket than a regular die handle would be under the dash. The threads were a little shallow since the OD of the link is about 0.020" smaller than a typical 3/8" bolt. (Be sure to measure your link diameter before you try this. Auto MFG are notorious for using what ever part they can get that's close to their design criteria.) Since the link is soft metal it threads easily. I cut the rod end theaded section in half to reduce the amount of work to thread and screw on to the link. I threaded my link in until it bottomed out. A couple drops of removable locktight keeps it from spinning loose.

Remove the right clutch assembly arm. My nut was swagged to prevent loosening over time. Shoot some lube on it and go slow. The arm has cheap splines holding it to the assembly shaft. Mark both before removal for proper realignment. You can pry the arm off the splines with a screw driver. Once the arm is off drill out the old pin to 3/8" ID. Tack weld the shoulder bolt so it won't spin in the arm.

Reassemble and enjoy one of the smoothest clutch actions you'll ever feel. I had to relearn how to use the clutch on my truck. Before if I didn't jam the pedal down it wouldn't shift gears with out grinding. Now I've got about 2" of travel off the floor before the clutch begins to engage.

One of the best fixes for the truck I've made.
Hope this helps.
Good luck!!

 

What a good post! Bumping for those who may benifit. Also, found the bushing on line for $14.

Anyone else attempt this repair?