John deere 4020 wont shift

[prairiefarmer]

I got an early model 4020, has been shifting a little rough and when you shift to 8th gear you would shift all the way into 8th and then have to bump gear shift up maybe 1/8 inch before letting clutch out or it would just grind and not go into gear. Linkage is getting worn so i thought I'd try to adjust it. Now ive got something outta whack. Tractor wont go into any gear whatsoever. If motor is NOT running, everything shifts fine and tractor will go into any gear. As soon as i start it any try to shift, transmission makes an awful grinding noise and wont go in any gear. If i put it in gear with engine off and hold down neutral safety switch tractor will start and stay in gear, BUT even if i push clutch down the tractor will not even try to stop, you gotta kill the motor. Is this a tranny problem, or clutch problem? Tractor was fine other than sloppy shifting before i tried to adjust this. I tried adjust linkage according to shop manual to no avail. What went so terribly wrong by making a small adjustment??

 

[wore out]

hold down neutral safety switch tractor will start

Sounds to me like you have a 4010 with a bad clutch.

4020 neutral safety switch screws into the left side of the transmission and you wouldn't be able to ''hold it down'', while the 4010'ss near the shift quadrant.

 

[Tx Jim]

Welcome to YT
I agree with wore out either clutch is stuck to FW/PP or ends of PP fingers are worn off where throw-out brg contacts fingers. Remove inspection cover under clutch housing in order to inspect finger ends, Another possibility is broken clutch finger operating bolt which visual inspection into bottom off CH would determine.

This post was edited by Tx Jim on 06/27/2022 at 03:59 am.

 

[Janicholson]

I also agree. Linkage issues can be fixed externally for the most part. the clutch is a different problem and compounds the shifter issue.
Likely a split to fix the clutch. Jim

 

[Northvale PA]

Someone mentioned the throw out bearing fingers. On my 4010 the throw out bearing seized and the
fingers burned off. I unseized the bearing, greased it and replaced the fingers thru the access port. It
was a temporary fix and eventually I did have the clutch replaced but can be done without a split if that
is the problem.