The Studebaker US6 (M16A) is a class of 2.5-ton trucks manufactured by Studebaker during World War II, produced in the United States from 1941-1945 and in the Soviet Union beginning in 1942.

The US6 had a Hercules built six-cylinder gasoline engine that produced 94 horsepower (70 kW), with a five-speed transmission plus a two speed transfer case. Production was divided between GMC producing trucks for the US Army, Studebaker Corporation producing 2.5-ton trucks for Lend-Lease, and International Harvester producing for the US Navy & Marines. Three primary manufacturers produced over 900,000 2.5-ton trucks in all, in both 6x4 and 6x6 axle/wheel versions, with approximately 200,000 Studebaker trucks built in thirteen variations, including dump truck and tractor models.

Studebaker trucks were unique from other 2.5-ton trucks built for the war effort because vent windows were included in each door. These windows were separate from the window that rolled down into the door and could be rotated out to help with ventilation.