In my opinion, the basic design is good. It could be improved in some area's as it is a 40 year old design. !!!
The 94 and 95 models used an aluminum front planetary that would fail even in normal use. 96 and newer is steel.
The main reason this trans fails is from a poor programing.
A fool at Dodge thinks we won't buy them if we feel them shift.
Good GOD we don't want a luxury car to pull our trailer etc. !!!
Almost every one who recalibrates them sees double or triple life.
A shift kit will fix most as they are from the factory, some need a little more experienced trans guys involved.
The other causes of failure are caused by the low RPM torque that the Cummins makes. This motor-when power is added-will in time over power any auto on the market today.
I have a 02 2500 4x4 and I upgraded it at 30,000 miles. It was slipping the clutches. It now has my idea's on the shift programing so we will see if I'm right.
The line pressure MUST be raised to ensure it has a chance to survive.
Some will lead you to believe other wise.
Again this is my opinion.