ANN ARBOR, Mich., June 10, 2010 -- Eight months after the launch of V8-powered Panamera S, 4S and Turbo models, more fuel-efficient Panameras powered by V6 engines have begun arriving in Porsche dealerships.

The 2011 Panamera and Panamera 4 have Porsche’s all-new 3.6-liter, 300-horsepower V6 engine with Direct Fuel Injection (DFI). The new V6 is built on the same line as the normally aspirated and twin-turbocharged 4.8-liter V8 engines found in the Panamera S, 4S and Turbo.

The new V6 Panamera gets 18/27 city/highway mpg. The all-wheel-drive Panamera 4 delivers 18/26 city/highway. Panamera S and 4S models get 16/24 city/highway; the Panamera Turbo model gets 15/23.

Porsche says that the new Panamera and Panamera 4 were developed with the Porsche Intelligent Performance philosophy, which means more performance on less fuel, increased efficiency and lower CO2 emissions.

U.S. models come standard with Porsche’s Doppelkupplungsgetriebe (PDK) seven-speed double-clutch gearbox and the Auto Start/Stop function that saves fuel and reduces emissions by turning the engine off when it is not needed.

Reducing weight is also a priority, as the V6-powered Porsche is about 66 lbs. lighter than the V8 model. The axles, doors, hood, front fenders and tailgate all all made of aluminum.

Like all Porsches except the 911 GT3 and 911 GT3 RS, neither the Panamera nor the Panamera 4 is subject to a gas-guzzler tax. Both also meet the strict EU5 emission standard in Europe and the LEV standard in the U.S.