General Motors Atlas engine
Atlas is a name for a family of inline piston engines for trucks from General Motors, used in the GMT355 and GMT360 platforms. The series debuted in 2002 with the Oldsmobile Bravada, and is used in the Buick Rainier, the Chevrolet TrailBlazer and Colorado, the GMC Envoy and Canyon, the Hummer H3, Isuzu Ascender and i-370, and the Saab 9-7X. The engines use GM's Vortec name, with straight-4, straight-5, and straight-6 engines all part of the same family, sharing the same manufacturing equipment, rods, pistons, valves, and other parts.
Source: Wikipedia — General Motors Atlas engine (CC BY-SA 4.0)