'03 Power

[Mike Fultz]

What I have noticed, and without data-just seat of the pants is that my '03 seems to get "sluggish" after much around town driving and being easy on the throttle. After I towed a 7500 pound trailer 750 miles, and through hilly terrain at 70 MPH--often hard on the throttle and solid downshifts I found the truck seemed to have much more power after I unhooked the trailer. I have checked the Throttle Position with a Tech2 and I am getting 100%. Could it be that the adaptive Ally and the ECM communicate so well that the ECM modifies the engine management to favor gas mileage over power when you seem not to be demanding it???

Mike

[a64pilot]

Yes, on all year models. I think most if not all adaptive tranny's will do this. Some for smoother shifts, maybe for fuel mileage also, However when the pedal hits the floor they all should allow the engine to be in optimum RPM for power.

[SoCalDMAX]

Mike,

I've got an early '02 (built 10/01) and I've noticed the same feeling - the truck seems to have quite a bit more beans immediately after unhooking the trailer. Here's my unscientific theory. ;) I figured it was just my seat-of-the-pants feeling based on *perceived* throttle input vs how the truck responds after unhooking 10,000 lbs of trailer. I figured if a normal passenger car feels peppier with only 2 passengers instead of 4, the disconnection of a trailer could really feel like a big difference.

On the other hand, the TCM does definitely shift firmer after some towing, so maybe during our normal commuter driving the TCM is slipping the shifts a bit for smoothness and we perceive it as a drop in power.

Dunno what the real answer is, but to me its just the difference between "peppy and peppier."

Regards, Steve

[Colorado Kid]

I tend to agree with SoCalDMAX as I've noticed the same peppy feeling after unhooking, and I don't have an Allison. I think the truck "feels" better because my pants-o-meter has been recalibrated while towing, or perhaps more accurately my accelrator applicator (foot) has become accustomed to big applications. . . the truck runs harder after a pull because I'm asking it to.

That's just my pet theory. . .each of us is entitled to our own.