Re: zf 5 transmission and clutch question
The clutch linkage for these truck is of questionable design, there are many flaws and trouble points.
Get on your back, under the steering column and inspect the linkage from the clutch pedal, the rotating shaft, the clutch actuator lever.
Look for a worn egged shaped hole in the pushrod of the clutch master cylinder.
The clutch resevoir is OK to open.
The Ford manual has written that a worn clutch will cause the level to rise. My common sense does not make this work, but just to warn you that the fluid level may be high.
'93 F-250 IDI, 4x4, K&N, no soup bowl, stock, with 265,XXX miles 5 speed, 3.55, kind of new LUK clutch, runs great, starts great, it is great. The truck is getting old.