That looks like a US Navy Freightliner FL80 crew cab. I spent many hours driving those between San Diego and the ranges at Camp Pendleton before my 2010 deployment to Iraq. The trucks we had like the one in your picture had Cat C7 engines , push button 5 speed automatic transmissions, air brakes ,and air bag suspensions. Not a ton of power, I think around 250 horsepower but i could be wrong. The inside of the cab was huge, would make an awesome family car. I preferred the older models we had, they had beam rear suspensions that worked better off road and seemed to have a bit more power, made accelerating up the freeway on ramps in San Diego a little less stressful at rush hour. I attached a photo of my favorite truck; it was the best runner of the lot.