The Hummer H3 SUV is a vehicle from General Motors\' Hummer division introduced in 2006 and based on the GMT355 that underpins the Chevrolet Colorado and GMC Canyon compact pickup trucks. Currently produced at GM\'s Shreveport, Louisiana factory and the Port Elizabeth plant in South Africa the H3 is the smallest of the Hummer models, and the first to be built by GM. It is available either as a traditional midsize SUV or as a midsize pickup known as the H3T. The H3 features a two-speed, electronically controlled full-time four-wheel drive system that is suitable for both on-road and off-road driving in all conditions, with electronic locking front and rear differentials optionally available. Like its larger sibling the Hummer H2, the H3 can ford 24 inches (610 mm) of water (tested in depths up to 31 in/790 mm) at a speed of 5 miles per hour (8.0 km/h) and 16 inches (410 mm) of water at a speed of 20 miles per hour (32 km/h). Standard ground clearance is measured at 9.7 inches (250 mm) while the approach, departure, and breakover angles are measured at 37.4°, 34.7°, and 22.1° respectively, allowing the H3 to scale a 16-inch (410 mm) vertical wall and negotiate grades of 60% and side slopes of 40%. Though fore and aft recovery hooks are standard, a trailer hitch and wiring harness are optional. Maximum towing capacities are 3,000 pounds (1,400 kg) for the straight-5 with manual transmission, 4,500 pounds (2,000 kg) for the straight-5 with automatic transmission, and 6,000 pounds (2,700 kg) for the V8 with automatic transmission. Cargo volume with the second-row seats in the upright position is 25.0 cubic feet (0.71 m3), which expands to a maximum of 62.8 cubic feet (1.78 m3) when the seats are folded down. V8 models feature the lightest maximum payload capacity of just over 1,100 pounds (500 kg) while straight-5, manual transmission models allow the greatest payload at 1,300 pounds (590 kg).