Two SUVs with some similarities, but otherwise different in most aspects such as the powertrain, horsepower, fuel economy, ground shadow size, height, and maximum occupancy. First of all, the 2015 Lincoln Navigator has bigger and thirstier engine; the 2016 Porsche Cayenne Diesel gets 6 more mpg. Also, the 2015 Navigator is both slightly larger and taller than the 2016 Cayenne Diesel. In addition, there is a difference in the number of passengers; the Navigator seats two more the Cayenne Diesel. Among similarities are the body structure, market segment, and starting price.