Ford 8n over/under aux trans won't shift

[Little Fred]

it works fine in whatever gear its in.... but if I try to put it in another range it doesn't work..... also if I go down a hill with a heavy load (two unloaded hay wagons) it will pop out of range (not fun) can I fix whatever's wrong with it without splitting the tractor again? someone said the detents might just be worn out.....
thanks!
 

[Bruce(OR)]

Sherman, Hupp, F&T ?
Which one is in there?
If the detents are worn/sticking, You get to pull it apart to fix it.
Just be sure to prefill prior to install.
 

[Little Fred]

Sherman
 

[Bruce(OR)]

You already have your answer. Now that your working on an N Tractor, it can be said, NJoy!