Mammoth is an automotive and aircraft company in the HD Universe.
Mammoth is obviously named after the prehistorical animal species, demonstrating the great size of their SUVs.
Mammoth also manufactures aircraft. Mammoth, like Western Company, Jobuilt and Buckingham, has a defense contract with the United States government, manufacturing various military aircraft for the United States Armed Forces. Their status with the United States Military could suggest they are also based on AM General (the makers of the HMMWV and Hummer before GM bought the brand), although the real-life AM General does not manufacture aircraft.