New Old Transmission

I just bought a used T 89 transmission with a D 20 attached for my truck. It is the cleanest transmission and transfer case I’ve ever seen come out of a jeep. The guy said it had probably been in storage for decades. It is so clean it has rust on it.

Anyway, it shifts into all gears and turns smoothly. Is there anything I should definitely check before I put it in my jeep?

 

I had to look up T-89 and sure enough, here it is:
The Novak Guide to the Borg-Warner T89 Transmission (novak-adapt.com)
But could your transmission be a T-98? That's the predecessor to the T-18.

 

The T89 is way more robust than the T90, T86, and the T14. It was the standard 3 speed used in the FSJ's, even behind the 327.

 

The T89 is likely comparable to the later T15 strength-wise. Every T89 I have seen has been a side-shift used with a 3-on-the-tree column shift. Maybe they had a cane shift application, similar to the T96 that was almost always side-shift, except in mid-60s DJ5’s that got the cane shift.
-Donny

 

My jeep is a 65 J 2000 with a 327. It actually came from the factory with a T 85 but I think that’s because it was built on the first day.