2005 Jeep Grand Cherokee Preview

So how does it work? Essentially MDS deactivates the valve lifters in four of theV8's cylinders (1, 7, 4 and 6), resulting in four closed valves and zero

The new Grand Cherokee being introduced at the New York International Auto Show in New York. The angular taillights are probably its most dramatic styling departure when compared to previous examples. (Photo: Trevor Hofmann, Canadian Auto Press)

combustion in half the cylinders. Fortunately the "dead" cylinders don't drag energy from the working four, due to air being pumped through those cylinders temporarily out of action.

Those who prefer fuel efficiency over absolute power can opt for an all-new base engine, the same 210 horsepower 3.7-liter SOHC V6 with 235 lb-ft of torque that is currently featured in the top-line Liberty. While the new engine provides smoother, quieter operation, greater power, better space optimization and improved fuel economy, it will be hard to say goodbye to the venerable 4.0-liter I-6, an engine that's been in the Jeep Grand Cherokee lineup for almost as long as I can remember. Bridging the gap, the efficient 4.7-liter SOHC V8 will soldier on with 230 horsepower and 290 lb-ft of torque.

No matter the engine chosen, all Grand Cherokees will feature a 5-speed automatic transmission, reportedly delivering smoother shifts and improved fuel economy in V6

The 2005 Grand Cherokee sports a more Jeep-like corporate face, meaning the Euro-style flush headlight clusters have been rounded to mimic the classically styled TJ/Liberty design language. (Photo: Trevor Hofmann, Canadian Auto Press)

and V8 applications. The unit mated to the 3.7-liter V6 will be all-new, while the current 545RFE 5-speed automatic will be joined up with the 4.7-liter V8 once again, and become the standard gearbox for the top-line 5.7-liter V8 as well. While it increases the SUV's maximum towing capacity Jeep also says it's been "refined for higher-quality shifts."

Part of that refinement is the addition of Electronic Range Select (ERS) driver interactive shift control in both transmissions, a first for the Grand Cherokee. In a nutshell ERS is another name for sequential manual mode, what Chrysler Group calls AutoStick in its other brands. This system is ideal for the Grand Cherokee, allowing easier manipulation of the gears during off-road use.