Results 1 to 2 of 2

Thread: 2.8 Duramax 6L50 to 8L90E swap?

  1. #1

    2.8 Duramax 6L50 to 8L90E swap?

    I am very new to tuning, and I'm wanting to see if this would be something possible to accomplish through HPT? I have a 2017 Colorado 2WD and am wanting to swap the trans to a 4WD 8L90e. The big reason for the swap is I plan on running a compound turbo setup, and the price of an 8L90 vs building a 6L50 to attempt to handle the power is astronomical. Plus if I can gain a few extra gears, why wouldn't I. I know that the V6 runs the 8L45 so the platform has an 8 speed, but I would really like to attempt to run the 8L90E.

    Thank you in advance for the newb questions!


  2. #2
    Advanced Tuner
    Join Date
    Aug 2016
    Short answer: Forget it, it's essentially impossible.

    Long answer: Even if any version of the 8sp transmission bolt pattern matches the 2.8 Duramax, which I doubt does, you'd have to find a way to make the Duramax engine control software communicate properly with the 8sp TCM (T87). It's unlikely anybody outside GM could pull that off.

    On top of that, there's no 8L90 OE application in this truck. It's unlikely the Colorado transfer case would mate with an 8L90 transmission.