The Stovebolt Site Forums The Shop Area Driveline '37 1/2 ton barn find

So after tinkering for six months I had the old girl ready for her first drive after 50 years on blocks. Shifting first to second went fine
but it locked up in second gear. It was stuck there so I removed the top cover and forced it into neutral so I could tow it back to the
garage. I put the shifter back on and it shifted fine from reverse to first but then locked up in second again. Any ideas? I have an
extra transmission I could try but I'm a little nervous about dealing with the torque tube. I have discovered that at some point someone
replaced the original engine with a 1952 (according to the casting number). The casting number on the existing tranny is 590874 and
the potential replacement is 590822. From my research they are both '37-'39 chev truck transmissions. So is there an easy fix for the locking
issue or should I swap trannys and learn to deal with the torque tube. Does it seem the other tranny will fit? Fortunately it's up on a
lift so I don't have to do this laying on the floor.
I'm an amateur at this whole deal but I'm having fun learning and appreciate all the help I've already gotten here.

Is the tranny lockup in the gears or in the shift rail? Shift rails can get rusty, full of grease, etc., if in the gears, might need to disassemble trans.

Ed

The shift rails appear to be smooth. I have to force it pretty hard to shift and it kind of "snaps" when it moves. Disassembling the transmission
takes me back to dealing with the torque tube. Am I unduly worried about how difficult that is? I've watched a couple u-tube videos and it
seems do-able if I can get all the parts.

The u joints on both my '37 and '42 are the type that cannot be disassembled on the truck. Thus, to drop the torque tube to remove the tranny you must remove the u bolts on the rear axle and using a long pry bar move the rear axle back about 6 inches (or as far as the flexible rear brake line will go). Also, unhook the parking brake. Then you are good to go. With a lift this is not all that difficult especially if you have help.

Regarding your extra tranny, I don't recognize the casting number so maybe it is a three speed? If so, it will be synchronized in 2nd and 3rd. The present tranny is definitely a 4 speed, non-synchronized.

In addition to shift rail problems, like stuck indent ball/spring, there is a soft metal shifter guide riveted to the underside of the shift tower. That part wears and may be the source of your problem, especially since you are able to put the tranny back into neutral. Just take the top 6 bolts off and take a look. If there is wear you might help by filing the guide to a smoother contour. The manual says to drill out the rivets and replace but I have never seen one come up for sale. You can take the shift tower off in the truck, after you remove the floor pan. Maybe start there in case you get lucky and that is the problem.

Kent

I googled the 590822 and it is for a 37 to 39 master deluxe. I wonder if it will fit the truck. I put the shifter from the other transmission on the truck
and it has the same problem so I'm thinking it's in the transmission. One of the other threads discusses how to detach the torque tube.
Looks like I'm going to have to learn more about torque tubes than I ever thought I'd need to know.