The GMC Canyon AT4X is the most capable mid-size truck for serious off-road use, and it wears that distinction with confidence. The 2.7-liter turbo four-cylinder produces impressive torque -- 430 lb-ft is more than some full-size trucks -- and the segment-exclusive Multimatic DSSV dampers, borrowed from Colorado ZR2 race trucks, deliver an astonishing combination of off-road absorption and on-road composure. Front and rear locking differentials, 33-inch tires, and multiple off-road drive modes give the AT4X genuine trail capability that goes well beyond the aesthetic pretense of most off-road packages. The interior is well-appointed with durable materials and useful technology. On-road, the Canyon drives with a refinement that belies its rugged credentials, with comfortable highway cruising and decent noise isolation. The trade-offs include a firm ride when unladen, a turning circle that complicates urban maneuvering, and fuel economy that suffers with the AT4X-specific hardware. At $55,000, it is expensive for a mid-size truck, but the off-road capability is unmatched in the segment.