The new 3.6-liter V-6 engine (originally called the Phoenix (earlier post) as late as Chrysler’s viability submission in February 2009) is part of a new family of V-6 engines to be built on a single architecture, representing the largest powertrain program ever undertaken at Chrysler. It will first be offered in the all-new 2011 Jeep Grand Cherokee, unveiled at the New York International Auto Show and at the Jeep Safari in Moab, Utah.

The new Pentastar V-6 is an all-new design, featuring a double-overhead cam (DOHC), narrow included valve angle cylinder head and high-flow intake and exhaust ports. This design, combined with dual independent cam phasing, allows optimum volumetric and combustion efficiency over the full speed and load range, resulting in a flat torque curve along with high specific power. The engine’s torque exceeds 90% of its peak value from 1,600 to 6,400 rpm—which will provide customers with outstanding drivability and responsiveness, without the need for premium fuel.

The engine delivers 280 hp (209 kW) at 6,400 rpm and 260 lb-ft of torque (353 N•m) at 4,800 rpm—an increase of 33% in horsepower and 11% in torque over its predecessor, while providing an 11% fuel economy improvement.

Low cost of ownership was an initial design requirement for the engine. The powertrain engineering team created an efficient design and integrated a host of technologies required for low fuel consumption, reduced emissions and improved refinement, as well as the considerable performance increase at a total engine cost comparable to the outgoing V-6 engines.

During the initial goal setting for the program, many of the “world’s best’ engines were analyzed to find functional targets, such as fuel consumption and refinement. The engine’s architecture also allows for future growth and technology applications.

The initial version of the Pentastar V-6 applied in the Grand Cherokee uses multi-point port fuel injection. Chrysler says that the new Pentastar engine meets competitive fuel economy and performance goals without direct injection. However, direct-injection, as well as other technologies, have been included in the future powertrain planning horizon for Pentastar’s engine family. Turbocharging is also a future possibility.

Nor did Chrysler opt to apply its MDS cylinder deactivation system in this first application of the Pentastar, although it is integrated into the Pentastar architecture. Chrysler said that the customer benefit in the initial application (Jeep Grand Cherokee) “did not justify the use of this approach, but it may in other future products.”

An advanced oil filter system eliminates oil spills and contains an incinerable filter element—more efficient disposal than the typical spin-on filters, which are disposed of in landfill sites. The use of long-life spark plugs and a high-energy coil-on-plug ignition system also helps to reduce cost of ownership.

The Pentastar V-6 is designed to run on regular gasoline, offering a 10% reduction in fuel cost compared with premium fueled engines. The engine also is fully flex fuel capable, offering consumers the choice of gasoline or E85 fuel without any degradation in performance or emissions.

The new state-of-the-art Trenton (Mich.) Engine South Plant will be the lead facility for production of the Pentastar V-6 engine. A duplicate, new facility in Saltillo, Mexico, will ramp up for the 2012 model year.

In the 2011 Jeep Grand Cherokee, the engine is coupled with the W5A580, a five-speed automatic transmission. The five-speed W5A580 transmission includes adaptive electronic control or Electronic Range Select (ERS) driver-interactive manual control and an electronically modulated torque converter clutch.