Raymond Lowe

The GM programming for the 6-speed can be pretty lame as the emphasis from the factory is maximum mileage (CAFE numbers). Back in 2008, the two biggest complaints were the truck not down-shifting quick enough up slight hills and a long delay downshifting when you punched it above 30mph (think on-ramp). GM came out with a transmission program (a TSB) that helped somewhat but it didn't cure all. Getting an engine tune helps smarten up the shifting quite a bit. Getting an engine/tranmission tune via the AutoCal is the ultimate answer. You actually download a separate transmission tune file that smarten's it right up. If I'm climbing a hill and depress the pedal even a smidgen, it drops a gear instantly. Seamless! I don't know why GM doesn't have this solved yet. You would think they could add a switch similiar to the "Tow/Haul" button for performance or "Sport" mode like Toyota used to offer years ago, and maybe keep their CAFE averages.