Hey Terry, I made it over here. I'll see what I an do about the TCM/ECM TAC stuff.
Are you sure its a 2004 Allison? What is the trans out of? What engine was in front of it stock?
I ask because there was a few years where there wasn't a 6 speed Allison available in the GM trucks, only a 5 speed Allison. We have to set this beast up using the parts from where the trans came from, not what you want it to be like. If the trans is from a 1 ton Suburban, you dont want to set it up like a gas pusher.
I realize that you have a 2006 wiring diagram , Workhorse R26 UFO Chassis 81L 2006, but we need to know exactly what Allison transmission you have sitting there. What vehicle did it come out of? You said the VIN was 1F6NF53Y560) the "0" signifies a 2006 vehicle, but then you said you were lied to and it might be might be from a 2004 1/2?
Are your 8.1 engine and Allison trans from different vehicles? We can control the 8.1 easy enough, it will run using any 1999-2007 PCM/ECM so long as we use the 24 x crank signal and 1x camshaft signal from the 8.1 and send it to the ECM?PCM.
The tricky part is sending the correct info from the ECM to the TCM, that's why we need to know exactly whaty the trans is.
OK I gotta take a break, supper time for me up here. Been at this for 5 hours now.
I'll check in later.
peace
Hog