GMC Full Size Truck... WTF?

My buddy just got himself a new GMC full size truck, with a 6L.
Now this thing has the electronic gas pedal. He let me take it for a spin and said to give it hell. I find that with this truck it seams like there is
a whole lot of power, but I can't seem to get to it. It seemed to me like it wouldn't downshift when I went WOT. So whats up with this?
2002 GMC Sonoma ZQ8 SLS Step-Side Extended Cab - 4.3L Vortec / 4L60E
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