T90 Pops Out Of First?

Ok, I'm confused by this one. The T90 in my 56 CJ5 pops out of first gear. Would it be as simple as a bad poppet ball in the shift rail? It doesn't pop out of second and it has been rebuilt. It doesn't feel like there is much holding it in first like my other t90s that I have. Occasionally when driving, I can grab the shifter and pull it back to where it needs to be.

 

If it has a poppet ball you might have a broken spring. Had this happen on my T-case a week after reassembly. Otherwise even though it was rebuilt the shift fork and or gear might be worn enough(not fully engaging) to cause the issue.

 

Is it under power, during coast, or any random time? Like when hitting bumps?

If it’s under power or coast, a bearing might be bad. The first/reverse gear is straight cut, so the only way it would want to squirt one way or the other is if it’s not parallel to the cluster gear.

Randomly or over bumps would point to the shifter.

 

It seems more random than anything else. I have another t90 and it takes some effort to shift it out of first. Maybe I’ll throw the top cover from that one in the cj5.

 

Years ago, I had a T90 that would jump out of 1st. When I pulled the trann/t/c out, the pilot bearing in the crank had come out of its bore and was jingling around. It also took out the front bearing, breaking the rivets holding the cage together.
-Donny