[unclebilly]

Almost all modern pickup trucks have variable displacement engines of one form or another...

GM and Chrysler are MDS which knock out cylinders when the power is not needed. Ford has turbo charged engines that have a constant displacement but the turbos and engine management system controlled fuel injectors pack in more or less air and fuel to result in the required amount of horsepower based on driver inputs. Toyota still has the 5.7 liter from 2007 with no gizmos... until late this year when it is rumored that they will have a hybrid drive system like a McClaren P1, Porsche 918, and Ferrari LaFerrari... small fuel efficient engine for cruising and combined electric / internal combustion for when the power is required...