What is this Adaptive learning process that the Allison tranny uses? Does driver behavior make a difference? I purchased my truck used with 40K. Just wondering what, if anything, this adaptive learning process may have to do with my truck? Thanks all!

The computer has full control over the speed that the trans performs each shift. The allison engages and disengages clutches on every shift, unlike many transes in the past that added engaged clutches as it shifted up through the gears without disengaging any. Consequently, when the next ratio is desired, the trans has to disengage one clutch while engaging the other. If the first clutch is disengaged too long before the next clutch is engaged, you get a rev up of the engine between gears. If it is too slow, you get a bind up because two ratios are engaged at the same time momentarily. So the computer looks at the way the engine responds during the shift and can adjust the way the shifts occur with trimmer solenoids. The computer has preprogrammed tables for reference, and it tries to make the shifts resemble that table for optimum durability and drivability. It wants them firm enough to not slip the clutches more than necessary, but not so firm as to make jerky shifts. When the truck is new or the learned stored values have been lost, it has to relearn how to make good shifts. When you add power by electronics or propane, it also has to learn to shift quicker to handle the extra power without slipping too much. However, it can only compensate so much. So if you add a bunch of extra power, you still need to upgrade the trans to handle it. So, the way you drive the truck certainly does influence the way the trans learns to shift.

WOW! This is pretty cool! I have not added any extra power and don't plan to at this point. Any advice or information I need to know or just get in and drive? I will eventually be pulling a trailer (10K lbs).

I would drive it a little bit agressively to have it learn to shift crisper. One thing I learned on mine is that tow/haul mode has its own values to learn. I had at least 6K miles on mine before I drove it more than a tiny bit in tow/haul, and it was like it was brand new. Slidey shifts and rev ups between gears. So, drive it in tow/haul before you get the trailer so that it can at least partially learn your driving habits before putting it to work.