1967 JD 4020 powershift transmission sudden failure

[owens73]

I have a front end loader on my 4020 and was using it to push some trees and brush I had cut months earlier. Transmission working fine one second, then moved the gear shifter to reverse and nothing happened. Transmission will not engage in any gear, forward or reverse. Was told of a switch below the rear axle that may have been moved by some of the debris I was pushing. If that's a possible solution and since I'm an hour away from the tractor, I wanted to know if someone knows exactly where this switch is before I go up to work on it. Thanks.

Steve

 

[Tx Jim]

It's not a switch but a disconnect lever for towing purposes. It's located on LH rear of floorboard. Another possibility is a stripped hub on damper clutch at flywheel. This damper clutch also has a disconnect lever(cold weather starting aid) on LH side of dash. Be sure it's not disengaged.

 

[owens73]

Thanks. I'll try that.

 

[jd110]

Also look at the rear axles where they attach to the wheels. You could have stripped the keyway on one side and the axle would spin inside the wheel without the tractor moving.

 

[stuckmotor]

Do the axles, on that big tractor, really have key ways?

 

[Tx Jim]

Yes the key is built into the wedge. I've never seen one stripped. Another thought is the possibility of a pinion shaft failure in the differential. If tractor has diff lock try depressing pedal ans see if tractor will move.

 

[stuckmotor]

Thanks, Jim. I learn something every day.