T90 To T18 Swap

For those who haven't been following the Colorado epic thread, I'm having clutch and/or trans issues with my CJ. This is a 70 with a stock 225 and cable operated clutch setup, with a T90J & D18 with a Warn overdrive.
Basically, I can start the engine, depress the clutch, and I can shift into any gear without a problem. So, I put it in 1st, drive away, and when I try to shift most of the time I can't get it out of 1st gear! When I can shift out of 1st, it won't shift into 2nd. There's no grinding or anything, it's just like 2nd isn't there. Same with 3rd. I don't think this is a clutch problem because I can shift while at a standstill no problem. I can also shift the overdrive while in motion with no issues. But I've never seen a transmission act this way.
Any ideas?

 

I would say a problem with the shift forks or maybe the synchros are ate up. Have you done anything with it or even had a look inside? If the clutch operates as it should I think you can rule that out. what about reverse? 1st and reverse are on one fork and 2nd and 3rd on the other

 

Synchronizers, dogs or shift tower.

 

Originally, yes.
Oil level is good.

 

I don't "think" it's a synchro issue...1st gear in a T90 is non synchro.

 

Binding input shaft bushing?

 

I forget who it was . and it had to do with a T14
front bearing retainer had come loose

 

I would remove the transmission cover and take the shift tower off and inspect the internals for anything wrong. Also it could be a roll pin the holds the shift forks to the rails could have backed out and might preventing the forks from shifting properly

 

Can you start out in 2nd or 3rd?
Sounds like a synchro assembly issue if it is fine at a stop.

The Trouble-18 would definitely fix the issue.

 

The way I'm reading it you say you sometimes can't get out of first to neutral. I don't think it's a clutch issue. You can push a transmission out of gear even without depressing the clutch. I would think your issue lies in the shift tower or some issue on the main shaft that gives too much freeplay.

 

That scares me....I don't want to kill my overdrive!

 

you can probably check the nose cone tightness through the access hole just have to get the clutch fork loose and out of the way. But thats probably not the problem because it would leak alot I would think

 

Fix the T-90 with a T-18!

Some info that may be of relevance or not..
I one time put a T90-j input into a T90 that had a T-90c cluster... Well it didn't work in the sense that it would not shift into 2nd or 3rd. First was fine, clutch worked like yours.. So, You have something that has let loose in your transmission. Pull the shift tower and take a look in there. Also, dont be afraid of tearing into a T-90. They are easy to work on, light and you can get all the help fixing or repairing one here. I did my first rebuild in my back yard in Arizona 25 years ago with just basic hand tools.

 

I rebuilt this one, about 20 years ago, and it's been working fine till now. I wasnt doing anything abusive when the problem started, we'd stopped for gas in Buena Vista, and when I pulled out of the gas station, I couldn't get it to shift.

 

I pulled the top. Everything looks good, but I can't move the 2-3 synchro at all.I think I should be able to move it by hand even if I have to move the shafts around a little bit, but I can't get it to budge at all. I'm not sure how that relates to the 1st gear problem, as the 1st reverse gear slides easily.

 

How do the shift rails in the cover look?

 

Good