4th gear walking out

[johndeerered]

I’ve got a 720 that will slowly walk out of 4th gear. If you slap it in pretty hard it will stay. Is there any thing that locks it in like a ball and spring to keep it in place or what do I need to look for. The lever also walks out with it, a little bit of pressure and it will stay also. Any info is appreciated

 

[Scott 730]

Yes there are detent balls and springs, but the root cause may be worn or loose bearings on the lower countershaft. They are tapered roller bearings and if they have too much end play it changes the alignment of the countershaft and upper shaft gears. I had this same issue on my 730D. I was into my trans for a different issue, and decided to remove shims to take up the wear in the cs bearings. This made my stick walking even worse, as I suspect the gears had years of wear on them and putting the cs back in alignment didn't play well with the worn gears. I cut a piece of 3/8" plywood to slip in the slot to hold the stick in place. I know, not the right thing to do.

 

[JIM MN]

Worn teeth on the 4th drive and driven gears. The shifter shaft has locks on the shaft. Locks can be worn or broken lock springs. Is it just 4th gear it is walking out of?

 

[johndeerered]

Worn teeth on the 4th drive and driven gears. The shifter shaft has locks on the shaft. Locks can be worn or broken lock springs. Is it just 4th gear it is walking out of?

Worn teeth on the 4th drive and driven gears. The shifter shaft has locks on the shaft. Locks can be worn or broken lock springs. Is it just 4th gear it is walking out of?

Yes just 4th gear