GM is going to need the Duramax to produce at least 825ft lbs of torque and tow around 30,000lbs to be competitive (on paper) with Ram/Ford.
Show me an 8L90 that will hold 825ft lbs while towing 30k lbs and Ill show you a Duramax that can fly.
Seriously, Ill bet you guys a million dollars that the Allison is not going anywhere.
So GM now uses a different controller for the Allison, so what. Car mfg's switch/update controllers for all sorts of different reasons.
The A40/A50 4th gen Allison controller is 10 years old and was/is at the end of its life-cycle and needed to be replaced to add additional/future features with faster processing and more advanved logic. The replacement is the all-new Allison A61 5th gen controller. GM probably didnt want to pay Allison to write them all new code for the A61 and license the A61 for use in the GM pickup trucks.
At the same time the 4th gen A40/A50 was at its end-of-lifecycle, GM released a brand new (and very capable) transmission controller for the 8L90.
The bean counters did the math, and it obviously was cheaper/made more sense to use the new T87 for the Allison as the replacement for the A40/A50 in the pickup trucks, rather than use the new A61. Less hardware to support/stock (8L90 and Allison now use the same computer), less connectors to supply for wiring harnesses, and probabaly less work in the software/calibration department because GM can do it all in-house and only one team is needed (the "T87 team").
So, in summary, switching to the T87 on the Allison doesnt mean jack shit. :thumb: