I'm far from a mechanic but know enough to be dangerous. Our mechanic at work is on vacation so there having me fill in. Problem I'm having is we got a 1978 f700 lift bed truck that has a Clark manual transmission model 282v67 that will only stay in 1st gear. But I can put into reverse and the back up warning sounds. When you let off the clutch it only wants to go forward though. When I put it into neutral the same thing happens as I release the clutch, goes forward. I was told that this has happened before numerous times to this truck and our mechanic gets underneath the truck and can pop it out of gear somehow and it works fine. This happens only when the lift is up and the driver decides to move the truck at the same time for whatever reason. I really don't care what's faulty, just need to know if anyone can tell me what it is that our other mechanic is doing to disengage the transmission by hand. Im not familiar with manual transmissions and know on automatic trans your able to **** in and out of gears by the linkage on the trans. Can and how is this done on a manual. Its driving me crazy cuz the guys here make it sound like he just climbs under and can pry it into neutral with no problems. I've been under the truck for a day and a half. Any help would be greatly appreciated.

 

Does the truck have a PTO? It most likely does as a way to drive the dump bed. Maybe that is what is jamming the transmission in gear. I was always told that you should be in neutral to operate a pto. Maybe that is what your mechanic is prying loose when he is under the truck. Does the transmission shift and otherwise work correctly? Anyone else with more experience with PTO's?

 

Yes it has a PTO and it seems to be disengaged. I can freely turn the pto shaft with no problems by hand and can also pull the lever that locks it in, just fine... it won't engage anything until I let off the clutch which I can't cuz its stuck in drive.

 

Dont know anything about clark trannys but dont get under the truck and let it roll over you.