The trucks we drove were stock versions, with no side rails or brush bars and with 9.3 inches of clearance in front and 8.4 inches in the rear, according to GM’s specs sheet. At least three times each truck needed spotters to help even experienced off-road drivers with tire placement so we could get over particularly challenging obstacles, and even then there were a couple of good whacks against the bottom of the 355s’ frames.
The new trucks ride on wheelbases that are three inches longer than the previous model and the vehicles themselves also are longer, by as much as 2.2 inches. Passenger compartments also are longer, and wider as well, thanks primarily to better sculpting of interior door panels, which still have room for both map and beverage pockets.
The Z-71 suspension puts torsion bars on the independent front setup with a live axle and leaf springs in the back. We were impressed at how well planted the rear end remained as it kept the tires in good contact with the rarely smooth surface of the trails. It basically was if we were driving well-engineered sport utility vehicles, which we mean as a compliment when applied to pickup trucks, off or on pavement.
The push-button four-wheel-drive system with 4HI and 4LO settings also did a nice job of putting the inline five’s grunt to the ground, even getting us up some steep climbs on loose rock surfaces that led to narrow but scenic routes along ridge lines and shelf roads.
GM worked hard to provide a second throttle map for proper response when the Colorado and Canyon are in 4LO, though the vehicles are so capable that we did nearly all of the trails in 4HI.
One key, one of the engineers explained, is that the new frame is so stiff – 250 percent more resistant to torsional flex -- that suspension could be properly tuned “to control the body and not just shake.”
Indeed, only extremely uneven surfaces caused much head tossing in the trucks’ cabins.
The trucks were impressive, and so was the setting, just 60 miles southeast of the downtown business district of the country’s fifth-largest city.