I've got a 1989 F250 351w with a five speed and 4x4, with less than 87,900 miles on her. The previous owner said she is drive able, but I have found out otherwise. She runs fine, so I'm not worried about that. I can put her into gear with or without the clutch from a standstill, but she won't grab any gears and get moving. She won't even jump forward or backwards, in ANY gear. She doesn't stall out when I let out of the clutch. I don't know if it could be the clutch master or slave cylinder, the linkage arm may need adjusting, or anything else. I'm sure I'm leaving out details, so please ask any questions that may help with diagnosing my truck. Thanks!

 

Normally, the clutch is engaged with the engine unless it is released by depressing the clutch pedal. If you attempt to shift into any gear with the motor running ,without disengaging the clutch you will hear gear clash and all sorts of noise which will get your attention and cause you to stop attempting to put the trans into any gear.
If for any reason the clutch pressure plate does not move the clutch disc against the engine flywheel that connection between the engine and trans is broken (separated).
When the connection is separated you can generally shift the trans into gear.
What you can try is to remove the flywheel cover 4 bolts and look at the clutch assy.
There may be a problem with the linkage being frozen and not allowing the release bearing to release the pressure plate and disc to contact the flywheel. When you look in there you should see the action take place when someone depresses the clutch pedal , motor does not need to be running to do this. You would also be able to see if the disc is not contacting the flywheel with the pedal released. The hydraulics are used to release the clutch and apply it when allowing the pedal to come back up.
Hope I shed some light on the problem without getting too windy !

 

Nice hanky. agreed with you !!