Hard to shift transmission



Hey all; need a bit of help.

My truck (1993 f-250, 351W with the 5-speed manual. ZF S542 Is the tranny I have. 4wd, newly redone driveline)

This morning, I started to have a really hard time putting the truck into gear. Usually forward gears with the exception of 3rd (typically kinda sticky) are usually very smooth and have little resistance to get into. There is some which is normal given age, transmission, and application.

I just had the driveline redone, (driveshaft, u joints, carrier bearing) would this in any way or shape or form cause this issue? Im thinking clutch or transmission, but more clutch than anything because its never been replaced after ~159,000 miles.

It doesn’t seem to let me upload a video so y’all can hear the sound it makes and how much i struggle to work gears. It seems to have gotten easier when it warmed up to a balmy 34 F … it was 11F when it started.


The problem might be with the clutch master cylinder.

If the clutch master cylinder is leaking internally, It doesn’t fully disengage the clutch because of the lack of hydraulic pressure. So it would cause hard shifting.

If you can shift thru the gears without the engine running, but find it hard to shift while the engine is running and stepping on the clutch pedal, it points to a master cylinder leaking internally.



It might be the clutch master cylinder. Suggest to start there. If pumping the clutch pedal, fully down and back up again, if doing that several times before attempting the shift seems to help make the shift easier, that’s consistent with a bad clutch MC. Heating and cooling the clutch MC can be diagnostic too. Try wrapping an ice pack around it, see if that has any effect. If heat or cold applied to the clutch MC affect the shifting, another indication the clutch MC needs to be replaced.


Update: the clutch seems softer than usual, its also sticking halfway up from time to time. Would that be consistent with clutch master cylinder issues?

Update ~4hrs later: I finally had a chance to take a peek, clutch fluid was low. Filled it up and it shifts a whole lot better. Now I just have to wait and see if it leaks again then ill know for sure. Anything else to check for a leak that might be a little less obvious?


Could also be slave cylinder.


Look on the inside of the firewall, where the clutch pedal rod passes thru to see if hydraulic fluid is leaking down under the carpet.



The clutch fluid level doesn’t usually change much over time unless there’s an external leak. Tester’s advice above is spot on, as that’s a common place for a clutch MC to spring an external leak. If you continue to have problems with shifting, bleed the clutch hydraulic circuit. You may have got some air in there when the fluid got low. That is usually a pretty simple job for a shop. On my Corolla, 10 minute job.