The Allison 1000 Series automatic transmission is available in 5 vocational calibrations. The 620 ft-lb torque capacity of the standard Allison 1000HS leverages the full power of today’s high-torque engines. Optional power takeoff capability is also available.

With a tighter turning diameter than many passenger cars and pickups, a setback axle and a wheel cut of up to 53 degrees on 2WD models and 45 degrees on 4WD models, the GMC TopKick offers added maneuverability, minimizing hazards and increasing your productivity.

The TopKick's dramatically sloped hood provides forward visibility of the ground that is only 13 ft from the front bumper - that's twice as close as the Ford F-450.* And backing up is a breeze with 126 square inches of mirror surface, including a convex section, on both sides.