When the need arose for brisk acceleration or a steep hill climb - or, worst-case scenario, both at once - my test Acadia's transmission refused to shift to a lower gear until the engine felt like it was just about to give out from the strain.
When it finally did downshift, it was with a jarring "whoomph!" as the Acadia lurched ahead. That's not the sort of performance one expects of a six-speed.
GM said the transmission was tuned for the best possible fuel economy, which is why it hesitates to downshift unless it's really needed. At an estimated 20 mpg in overall city and highway driving with all-wheel-drive, the Acadia's efficiency is admirable, but I think GM engineers may have dialed out a little too much performance.
The Acadia's all-wheel-drive system is fully automatic, but it's not intended for serious off-roading. In ordinary driving, 90 percent of the power goes to the front wheels. If wheels start to slip or slide, up to 40 percent of the power can go to the back wheels.