The new 2015 Ford Mustang may have just been unveiled, but speculation regarding future models is already beginning. We're not just talking about the rumored Mach1 or Shelby GT350; this latest gossip is on the greener side of things.

At the 2015 Mustang's unveiling, Ford Motor Company [NYSE:F] global powertrain chief Bob Fascetti told GoAuto that the Blue Oval is considering diesel, hybrid, and even electric powertrains for future Mustang models. Fascetti didn't give any specifics, only saying that Ford would consider all options when it came to improving the Mustang's fuel economy.

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While most people probably don't buy a Mustang for its mpg, Ford does need to consider Corporate Average Fuel Economy (CAFE) standards, which require all automakers to achieve a fleet average of 54.5 mpg by 2025. Mileage-conscious consumers will get more models to chose from in the bargain.

Ford is already taking steps to make the Mustang less of a gas guzzler. The 2015 model will launch with a new 2.3-liter EcoBoost turbocharged four-cylinder engine. The first Mustang four-banger since 1993, it will produce an estimated 305 horsepower and 300 pound-feet of torque, and will be the car's mid-level engine option.

A 3.7-liter V-6, producing an estimated 300 hp and 270 lb-ft, will continue as the base engine. A 5.0-liter V-8 with an estimated 420 hp and 390 lb-ft will sit at the top of the range, at least until the arrival of Shelby and SVT-enhanced models.

Ford is also expected to replace the current paddle-shifted six-speed automatic transmission with a nine- or ten-speed unit co-developed with General Motors. A six-speed manual will continue to be offered, though.

Every car needs to change with the times, but a diesel, hybrid, or electric Mustang could be quite a shock (no pun intended) to the car's loyal fans.


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