Have you confirmed that the AW4 will work with your setup? I'd be interested in a future build to replace this 4.0

Who is using an AX4? Did I miss something? If you want to try, that would be cool, and I really would like to see someone accomplish it. So far the only type of swap I've seen suscessfully use an AW4 is to put it into a YJ or TJ Wrangler - because you can splice into the existing wiring harness.

The trouble with the AW4 is that it is electronically controlled. While it has its own separate computer - the Transmission Control Unit (TCU) - I believe the TCU gets its shift signals from the main engine management computer. The main engine computer uses signals from the Throttle Position Sensor (TPS) to measure how hard you're stepping on the gas, and the Crank Position Sensor (CPS) to measure engine RPMs. It then tells the TCU to shift the tranny based on those inputs. So, to use an AW4 you have to mimic the TPS and CPS signals and feed them to the main computer and then let the main computer control the TCU to shift the tranny. I may be wrong about the TCU being controlled by the main engine computer, and the TPS and CPS signals may go straight to the TCU, in which case you could do away with the main computer. But even if that's the case, you still have to mimic the CPS and TPS signals so it knows when to shift, so it gets pretty complicated.

The GM 700R4 is a good alternative - it is also a 4-speed auto with OD and a locking torque converter, but it can be set up with no computer to mess with because its shifting is controlled hydraulically and with a kick-down cable, and when you're using an old-school diesel with no computer control or sensors, that's a good thing. The only thing you have to add is a switch to lock up the TC - if you want to use the TC lockup. That is normally computer controlled, but can easily be done with a switch. I'm using one behind my GM 4.3L diesel, and my plan for the TC lockup is to use a momentary pushbutton to activate a self-latching relay with a NC brake pedal switch to break the relay latching circuit. That way when I'm on the highway I can just tap the button to lock the TC and it will stay locked until the first time I hit the brakes. It will also allow me to lock the TC in any gear. A simple LED indicator light will light up when the TC is locked