A device and method for adjusting vehicle fuel efficiency to responsive to an altered vehicle surface area are disclosed. An operation of the method receives vehicle surface data, which indicates a transition from a first vehicle drag coefficient value relating to a vehicle surface area to a second vehicle drag coefficient value relating to the altered vehicle surface area. A second plurality of powertrain parameter values associated with the second vehicle drag coefficient value are determined, and the method operates to transmit the second plurality of powertrain parameter values for adjusting of the vehicle fuel efficiency.