The GMC CCKW

Many features found on WWII CCKWs were part of the Military standard Specifications set forth by the Ordnance, and all tactictal vehicles were required to have them.
The Military lighting System with the special light swithh was one, Keyless ignition was another, Budd Wheels was another (they enabled the use of Duals on Front if the situation called for it). The Military 4" Gas filler Pipe, Spare Gas Can Brackets, Ventilating Windshield, Troop Racks, folding Windshield, Radio suppression, H.D. Military Charging System,Pintle Hooks, Tow Hooks, NDT tires, Data plates, Reflectors, Oil Can Bracket, Oil bath Air Cleaner, Military Senior Oil filter, Fuel Filter, Cargo Body, etc. The list is long.

The esthetic features of the CCKW Cab and fenders are a product of the Military Standard Spec, but are a General Motors concept.

I kind of like the way all CCKW types looked.

Stay tuned.

Then that answers the question as to why the Dodges and jeeps had similiar or identical equipment on their vehicles.

And all GIs had the same gear.
FYI the Gas Cans and brackets were not Ordnance responsibility, but were Corps of Engineers responsibility, the can was classified as a Drum.