Hi everyone, im new today, and this is my first post.

So i have a 94 f250 diesel in a manual. I love her, but there is one issue.
When i try to put it in reverse, i put the clutch all the way in, and put the shifter to reverse. If i merely place i there and don't worry about it, i let the clutch out and it will fail to engage reverse and instead grind.
If i pull the shifter down har and try to hold it in, it will engage reverse about 40% of the time as i slowly let the clutch out. 60% of the time it does as i said above.
The grinding slows and stops when i put the clutch bak in and i can try again.

Anybody who can help me? Can it be fixed? Can it be avoided? Help!
Thank you!

 

Try putting the truck in second then pull it out and go straight to reverse with out the clutch being released.

 

I have been told that by someone else, so you must not be crazy, but why would this work??

 

There are many reasons these ZF's have trouble going into reverse.
First I would check for a worn pedal bushing (4 finger white plastic clip) and firewall flex of the master cylinder.

If you know the disengagement is good (5/8 or more at the arm)

Then it could be worn shift fork pads or synchro's.

Here is the factory troubleshooting manual.
https://www.zf.com/na/content/media/...g_ZF_S5-42.pdf

 

I'm sorry, but i am not quite a mechanic and i won't pretend to understand most of what you just said hahah.
So how easy would it be to fix for most of these things?

Thank you for your help though!

 

When you push the clutch pedal there are a few plastic bits that transmit that motion to where the actual master cylinder pushrod is depressed.

If you look above the accelerator pedal you will see the clutch M/C pushrod coming through the firewall.
There is a white plastic retainer that holds this to the pedal arm.
There are also a couple of plastic pivot bushings WAY up inside the dashboard.
-any or all- of this plastic can wear out.
If things get sloppy, the clutch won't disengage enough to get into reverse.

ALSO,
The firewall is known for tearing where the clutch master cylinder mounts.
To test for this, open the hood and watch the clutch master cylinder while someone else sits in the cab and steps on the clutch.
If the master looks like it is doing a wheelie you need to add one of the reinforcement plates sold by Ford or Terrapin Manufacturing.

If ALL this is good have a read through that troubleshooting manual or take the truck to a TRUSTED transmission/gearbox shop and ask them to evaluate it.

 

Thanks a lot!
I was worried i might have to rebuild the tranny or something

 

You might, but it is always best to check for worn bushings and firewall flex first!
These are common problems that are much easier (and cheaper) to solve.

 

Your trans gears 2-5 are syncronized as 1st and reverse are not. So putting it in second first then going to reverse it acts as a synchro for reverse. Post back and let us know what happens.

 

This is NOT a T-18 gearbox.
Even my T-19 had synchronized first, (and that was the super deep 6.32:1!)

The ZF5 is a fully synchronized gearbox.
You're welcome to read the troubleshooting manual I linked if you don't want to believe it.

Maybe the synchro's is your ZF5 gearbox are shot?

 

Hey guys, so i have figured something out,
And now i get right into reverse every time!
The secret is hitting the clutch, then revving up a lil bit
While i shift in, then once i have it in reverse, i just continue as normal and it
Works! I don't know why this
Would be, but it makes me happy!

 

Did you read the manual?
Have you figured out why your clutch isn't releasing?
You do understand the synchro's are being eaten up because of it, right?

 

Just bought a used F250 and it has a similar issue, very interested to go check these options out, thanks for the info!