Today in WW II: 7 Aug 1942 US Marines invade Guadalcanal, the first major American offensive operation of WW II.   

GMC M222 Truck, Water Tank, 2 1/2 ton, 6x6 (G-749)

The M-222 2 1/2 Ton 6x6 Water Tank Truck is part of the GMC M-135 Series of Cargo Trucks. More information is found on the linked page.

U.S. Military GMC M222 Truck, Water Tank, 2 1/2 ton, 6x6 (G-749), from TM 9-8024
U.S. Military GMC M222 Truck, Water Tank, 2 1/2 ton, 6x6 (G-749), from TM 9-8024

U.S. Military GMC M222 Truck, Water Tank, 2 1/2 ton, 6x6 (G-749), from TM 9-8024
U.S. Military GMC M222 Truck, Water Tank, 2 1/2 ton, 6x6 (G-749), from TM 9-8024