DETROIT -- Cadillac will offer a plug-in hybrid version of the CT6 large sedan scheduled to debut late next year.
General Motors global product chief Mark Reuss said during an investment conference last week that the plug-in hybrid would get at least 70 mpg.
Reuss also said the CT6 will be powered by a six-cylinder, turbocharged engine that makes around 400 hp. He likely was referring to the 3.6-liter twin-turbo V-6 that debuted last year on the Vsport versions of the CTS and XTS sedans.
He said the CT6 engine will be mated to a stop-start system and an eight-speed automatic transmission, likely a version of the homegrown GM eight-speed that recently debuted in the 2015 Corvette.
The lightweight construction of the CT6 also will aid fuel economy. Reuss said the sedan will be 8 inches longer but 53 pounds lighter than the CTS.
Calling it "the world's most advanced body structure," Reuss said the CT6 will feature a mix of aluminum, high-strength steel and other lightweight materials. GM engineered the car to use 20 percent fewer parts than other vehicles of its size, he said.
Cadillac will position the rear-wheel-drive CT6 against the Mercedes S class and BMW 7 series. It will be built at GM's Detroit-Hamtramck assembly plant beginning in late 2015.