SPY PICS: New Mazda CX-7 spied

These are the latest spy shots of the next generation Mazda CX-7 caught undergoing testing in Michigan, USA. And although the camouflage appears to be concealing only a mild makeover the real story could be under the bonnet.

A diesel engine option has been a major talking point surrounding the CX-7 since its launch in Australia late in 2006. Currently only available with the company's 2.3-litre direct injection four-cylinder turbo petrol engine the updated model looks set to include the 2.2-litre turbo-diesel also used in the 6 range due in 2010. The spy pictures show only a single tailpipe on the new model -- instead of the usual double exhausts -- suggesting a powertrain change.

Although he stopped short of confirming a diesel variant for the new model Mazda Australia spokesman Glenn Butler told the Carsales Network that a diesel is certainly on the agenda.

"It's something that we want," says Butler. "We're making a lot of noise in Japan about it."

The sticking point appears to be the transmission. Mazda currently doesn't have an automatic transmission capable of working with the diesel engine that pumps out 400Nm. Despite some earlier reports that suggested a new automatic gearbox could be ready by 2010, Butler admits that may be "optimistic" now. It's more likely the new model will come to market with the company's current manual gearbox ahead of any automatic transmission.

What is known for certain is the new model will receive some cosmetic changes to freshen the three-year-old design ahead of a more significant update in 2013. The most noticeable changes are the much larger side air-intakes, giving the CX-7 a much more aggressive look. Tape is hiding the other revisions on the front fascia, as well as in the tail lamps, making it obvious that several minor tweaks are in-store.

With the car set for a 2010 on-sale date an official reveal of the new look is expected later this year, most likely at the Frankfurt Motor Show in September.

-- with Carparazzi