Powertrain Efficiency in the US Fleet on Regulatory Drive Cycles and with Advanced Technologies Patrick Phlips, Thomas Megli Ford Motor Company The powertrain efficiency properties of several technologies are studied by applying a first principles model to the large database of vehicles in the 2014 and 2015 EPA Test Car Lists. The model provides estimates for the ‘power-on’ and ‘power-off’ fuel usage. The fuel usage breakdown is computed using available powertrain and vehicle properties. The largest group of vehicles has naturally aspirated engines and six speed planetary automatic transmissions. The fuel usage per unit vehicle work on the City cycle is about 50% higher than on the Highway cycle. The individual ‘bag’ data show that the additional fuel usage is primarily due to the increasing amounts of power-off operation and secondarily due to a degradation of power-on efficiency. Also additional fuel is needed for emissions mitigation and warm-up in Bag 1. Advanced technologies being introduced to reduce fuel consumption are also studied. As the number of vehicles offered is lower, from fewer manufacturers and with lower technical maturity, the level of statistical definition is not as sharp. These vehicles are therefore evaluated by comparison to the well-defined base technology. It is found that cylinder deactivation and turbocharging with downsizing are mainly of benefit to vehicles with high power to weight ratios. In contrast, continuously variable transmissions are found to be very effective in small vehicles with low power to weight ratios.