The Stovebolt Site Forums The Shop Area Engine Shop 3 Speed Problem

Have a 41 1/2 ton 3 speed. Transmission has been rebuilt using all nos gears. Problem is it will not stay in 3rd gear under acceleration most of the time, feels like it is being pushed out of gear. It is going all the way into gear and shifting feels normal. Have pulled the top off the tranny and everthing looks fine as far as gears engaging. I am getting ready to pull the tranny back out, any sugestions would be appreciated. Thanks.

when the trans is in any gear there is a detent that should help keep it in gear You should feel a snap as it goes into gear most of the time the detent is part of the rod that holds the shifting fork there is a spring loaded ball in the trans and when You shift into a gear it will line up with a dimple on the rod that holds the shifting fork if the rod is worn out or the spring on the ball is weak or the fork is to close to 3rd gear it may not be keeping the fork in place also You gotto check to make sure that you check the adjustment best to remove the shifting linkage and push it into gear than see if the linkage lines up do that to all the gears and than at the same time You will be checking that ball and detent and spring You should feel a snap as it goes into gear and when You try to take it out of that gear You should feel a snap going out .When You installed the new parts did You readjust the forks they may look good but the 2nd 3rd fork may be to far on one side so that the rod is not lining up even a little will make a problem ?


Pete

The problem you describe could be misalignment of the input shaft. Are you sure it has a pilot bearing. If the pilot bearing is ok, check the clutch housing. Attach a dial indicator to the flywheel and turn it to check for runout on the clutch housing. If it has excessive runout, sometimes you can shim it against the block. The transmission should not be exerting pressure to try to jump out of gear. Clutch housings can get warped. You never know where your clutch housing has been the last 70 years. Someone may have bought one from a salvage yard that came from a burned vehicle. What prompted the rebuild in the first place? Was it doing as it is now, or did you just want everything new?

Pete52/crenwelge thanks for the reply. Discovered the input shaft was running to far forward, ended up machining a bushing backing it up .100, works fine now.

Glad You found it , Have fun, Pete