The only trans that will bolt in is the same model. You don't specify if its
a 3 or 4spd AT, but the majority of them are the 4spd AT. The 89 model
should bolt right in, assuming its the same model of trans. However, for the
price of a useable trans from a salvage yard, you may be able to get a
rebuilt one with some performance mods that would save repairs down the
road. These transmissions aren't any more problematic than other
manufacturers units, it depends on the use and abuse they are required to
handle. Can they be made better with some work? Absolutely.

I know I'm a day late and a dollar short in regards to this question
but I thought I would add this part anyhow. <g>

One thing to keep an eye out for (that I can think of anyhow) is if
the '92 is a MPFI vehicle. The MPFI system mounts the CPS (crank
position sensor) on the bellhousing of the transmission above the
flywheel. If the tranny from the '89 does not have the mounting hole
for a CPS then you could have problems.

As far as "some problems with these trannys" you might be thinking of
the mid 90's trannies. The early 90's trannies had regular mechanical
shifting mechanisms and were pretty much like the 904's/727's of the
70's. I have a '92 Dodge B250 van with a 318 Magnum. The tranny in it
is a regular 3 speed 727 with the mounting pad for the CPS. IIRC
somewhere around '94 or '95 Dodge started using a computer to control
the shifting of the trannies and from what I understand they had
issues with the solenoid packs. Another change with the mid 90's
trannies is how the speedometer is connected. When they switched to
the electronically controlled trannies they did away with the ability
to connect a mechanical speedo cable to the rear of the tranny. It was
made for an electronic speed sensor only.

Ruppster
http://www.dodge-semis.com/