Banks Speedbrake on a Duramax

To add to what I have already said, I found that the only use I have for the SpeedBrake is for towing in hilly terrain. I use it in auto and with the brake pedal feature disabled. This way it is only energized when I remove pressure from the accelerator and am over my set speed. Once the speed decrease below the set speed it disengages until the speed goes over the set speed. I found that it was too "busy" when used in any other mode, and there is a lot of ways to set it up. When traveling on the flat the truck's brakes and the MS's disc brakes will slow you down just fine.