The new TwinPower turbocharged four-cylinder that was introduced last year replaced the normally-aspirated six in the X3 xDrive28i; but it not only offered increased performance but significantly better fuel economy.
EPA for the xDrive28i now land at an impressive 21 mpg city, 28 highway, while the 300-hp xDrive35i earns 19/26-mpg ratings. Both versions reap benefits from an eight-speed automatic transmission.
U.S. versions now also get the Auto Start-Stop system, which wisely stops the engine at stoplights, with your foot on the brake, then restarts the engine when you start to lift off the brake pedal. We've found the system to be a little rough when the engine shuts off; but according to BMW in some gridlock and stop-and-go driving situations the system could result in a three-percent reduction in fuel consumption.