I've searched and couldn't come up with much, other than a lot of contradicting posts. I'm looking for the differences in the trannies themselves. I've been told the shift towers are different, the mainshafts are different, and some other minor stuff. I've driven a couple 24 valves with 5 speeds, and noticed a different shifter(straight instead of curved), and they shifted much smoother too. And are they interchangeable between the years? Thanks.

 

Completely interchangable, it's the same tranny.
The only thing different is the top lid which is also the shift tower assembly...but you can switch those too. The 98+ tower is what makes it an awesome shifting trans, the old tower sucks and feels clumbsy.

 

You will have to drill and tap the the holes for the transfer case shifter as the 98 shifter is mounted on the floor or use the shifter from a 98 and up truck and mount it on the floor

 

You will have to drill and tap the the holes for the transfer case shifter as the 98 shifter is mounted on the floor or use the shifter from a 98 and up truck and mount it on the floor. Above 98 the case cannot be drilled as there are no nubs on the trans in that case you will have to use the later mount.

 

Sometimes. I have a 98 that I bought for a 4x4 conversion and it has the 4x4 shifter in the floor but one of my employees has a 98 that as it mounted to the trans. I dont know what the deal is, I was hoping his was the same as mine so I could use it for measurements, no such luck.

 

You can also buy a short throw shifter for the 98+ trucks.