Gone is the Explorer’s off-road transfer case and maximum 7,115-pound towing capacity. For 2011, the Explorer is losing its truck chassis and getting a new unibody frame based on that of the Ford Taurus, Ford Flex, and Lincoln MKT. The Explorer will come standard with a 290-horsepower 3.5-liter V6 and can be optioned with a 237-horsepower EcoBoost turbocharged 2.0-liter four-cylinder engine that