http://www.globalsecurity.org/military/ ... nd/m35.htm
"Production of the GMC Truck, 2-1/2-ton, 6 x 6, Cargo, CCKW "Jimmy" or "Deuce and a half," began in 1941 by General Motors Corporation and ended in 1945, with 562,750 manufactured. This GMC truck was the most commonly used tactical vehicle in World War II. The GMCs were originally fitted with a sheet metal type cab. This was replaced after July 1943 by a tarpaulin or canvas cab, not only for the economic use of steel, but saving volume when transported by boat."
Can you find the errors?
First, the CCKW was never referred to as a Jimmy or Deuce and a half. It never appears in any documentation of the time, no quotes, films nada. Jimmy was the civvy slang for GMC trucks. Some have posited that the mechanics/drivers brought that slang to the Army. I doubt it.
The open cab (or canvas top, or Model 1619) started in mid/late 42. Closed cab production was all but complete by Mar/Apr 43
The GMC was the most COMMON VEHICLE or WWII. Nothing else came close to the 560,000+ produced. Not sure how it was used 'tactically'... it was a supply vehicle. I guess if moving a battalion/division from point A to B is 'tactical' then OK.
Then this gem:
"Crew-served weapons are the ones where the gunner has an assistant gunner that feeds the weapon and changes the barrel, so the shooter can concentrate on hitting the target. The M2 50-caliber is in a ring mount on top of a deuce and a half ton M35A1M1 truck. The M2 is used on what is called “a gun truck” that is designed for convoy security. The ring mount allows the Soldier who is firing the weapon to move 360 degrees. Rather than just firing out of the front of the vehicle, he can turn and engage targets all the way around. In a regular combat situation a transportation unit would use generally one gun truck per 20 vehicles in a convoy. "
The ring mount was first installed in WWII CCKWs. It was primarily an AAA device. A Divisional Quartermaster Company would have roughly 20-25% (one in 4) trucks fitted with an M2 .50HMG. There were three 'styles' of MG mounts, one for closed cab 352, one for closed cab 353, and one for open cab (352/353 - the ring was mounted to the cab, not the bed as in earlier variants).