Rear echelon based GI's, such as clerks, cooks, supplymen, (medical) aid station staff, wheeled vehicle personnel, aircraft mechanics & crews, normally had access to a 1/4 ton (jeep). Or they walked from place to place within the base; often catching a ride from some passing army vehicle. Line troops (Infantrymen, tank crewmen, cavalrymen, artillerymen, etc.) stayed with their outfits. If a trip needed to be made into town (a nearby village) for ice (a 3 foot long block of ice) to be divided up between tank or ACAV crews for their ice chests (army issue), then a tank, but normally an ACAV (Armored Cavalry Assault Vehicle-M-113 APC-Armored Personnel Carrier) would be detailed to ride into town and pick up the item(s). Infantrymen were usually stuck with a truck, for re-supply runs. Tracked GI's distained wheeled vehicles...they did not survive land mines very well. If a helicopter was beginning to take off, and you waved it down, they might give you a left. The door-gunner would pull back his helmet covering his ear and you would yell where you were heading, he'd say a few words thru his microphone, then either nod get on, or wave his hand, no he couldn't...you'd step back, and off they'd go.