Chrysler’s new V6 to power next Grand Cherokee

CHRYSLER has announced key details of the new Pentastar V6 that will make its debut in the entry-level version of Jeep’s next-generation Grand Cherokee, which goes on sale in Australia in January next year.

Claimed to be the most advanced six-cylinder engine in Chrysler Group Powertrain history, the 3.6-litre petrol and E85 ethanol-compatible V6 is expected to account for more than one-third of Chrysler’s total engine output.

Chrysler has also confirmed that future versions of the flex-fuel V6, which is forecast to contribute to an overall fuel economy improvement of more than 25 per cent for the company, will benefit from technologies accessed as part of Chrysler’s alliance with Fiat, including turbocharging, direct-injection and Multiair.

The number-three US car-maker says the new Pentastar V6 will ultimately replace seven Chrysler group V6 engines. Apart from the Grand Cherokee’s, these are likely to include the similar 3.7-litre V6 in the current Jeep Cherokee and Dodge Nitro, the 3.8-litre V6 in the Jeep Wrangler and Chrysler Voyager, the 3.5-litre V6 in the 300C and – eventually – the 2.7-litre V6 in the Chrysler Sebring, Dodge Avenger and Journey.



Left: Chrysler’s new Pentastar V6 in production.

“First offered in the all-new 2011 Jeep Grand Cherokee, launching (May) this year in the United States, our all-new Pentastar V6 engine allows increased flexibility to apply new technologies and enables significant cost savings for the company by substituting previous generation V6 engines,” said Chrysler Group LLC senior vice-president of powertrain, Paolo Ferrero.

The oversquare, all-alloy Pentastar V6 displaces 3.6 litres via a 96mm bore and 83mm stroke and in the 2011 Grand Cherokee, which emerged at the 2009 New York motor show, will deliver 216kW at 6350rpm and 353Nm of torque at 4300rpm.

Chrysler says that’s 38 per cent more power and 11 per cent more torque than its predecessor, while the Pentastar V6 is also said to use 11 per cent less fuel.

By way of further comparison, the 3.7 V6 that powers Australia’s Nitro and Cherokee offers just 151kW/314Nm, while the 3.8 V6 delivers 142kW/305Nm in the Voyager and 146kW/315Nm in the Wrangler. Holden’s 3.6-litre direct-injection V6 produces 210kW and 350Nm.

Chrysler says that thanks to its narrow included valve angle and high-flow intake and exhaust ports, more than 90 per cent of peak torque is available between 1800 and 6350rpm, “providing customers with outstanding driveability and responsiveness, without the need for premium fuel”.

In its most basic guise it comes with multi-point port fuel-injection, revs to 7200rpm and can run on either E85 or regular petrol with an octane rating of just 87 RON.

Chrysler says it benchmarked the industry’s leading engines to set functional targets for its new V6, which is claimed to represent “an ideal integration of select technologies that deliver exceptional refinement, fuel efficiency and performance”.

Comprising a high-pressure die-cast aluminium cylinder-block and semi-permanent mould aluminium cylinder-head, the 24-valve 60-degree V6 features double overhead camshafts with roller finger followers, hydraulic lash adjusters and dual independent cam-torque actuated phasers.

According to Chrysler, the engine’s advanced oil-filter system eliminates oil spills and contains an incinerable filter element for more efficient disposal than typical oil filters, while long-life spark plugs and a high-energy coil-on-plug ignition system are designed to reduce maintenance costs.

“Our engineers synthesised the best combination of design features and technologies to create a V6 engine that will exceed customer needs,” said Chrysler Group vice-president of engine and electrified propulsion systems engineering, Bob Lee.

“The elegantly simple design maximises functionality and provides class-leading levels of refinement, fuel-efficiency, performance and cost of ownership.”Chrysler launched the Pentastar engine last week at its Trenton South Engine Plant (TSEP) in Michigan. Chrysler Group announced a $US730 million ($A798m) investment in the Pentastar program when it broke ground on the new facility – which will have an annual capacity of 400,000 engines – in May 2007.

“The Pentastar engine is a cornerstone of Chrysler’s efforts to reinvent its business model with strong, brand-focused, world-class quality products,” said Chrysler Group head of manufacturing Scott Garberding.

The Pentastar engine will be followed by production of Fiat’s 1.4-litre, 16-valve Fully Integrated Robotized Engine (FIRE) engine at Chrysler’s Global Engine Manufacturing Alliance (GEMA) plant in Dundee, Michigan, for which the company announced a $US179 million ($A196m) investment in December.

“With the start of production here in Trenton and the recently announced investment in Dundee, Chrysler Group has helped affirm Michigan’s position as the world’s leader in automotive innovation and excellence,” said Michigan governor Jennifer Granholm.