Trail Rating for New Jeep Patriot Presents Challenges

SCOTTSDALE, AZ – Helping the ’07 Patriot meet Jeep’s tough Trail Rated standard was a tall order, so Chrysler Group engineers raised the vehicle’s height 1 in. (2.5 cm).

The Trail-rated variant of the all-new cross/utility vehicle sits higher than its platform-mate, the Jeep Compass, and features 9 ins. (23 cm) of ground clearance.

This contributes to its ability to ford water up to 19-ins. (48-cm) deep – a key attribute, along with ground clearance, that allows the CUV to wear Jeep’s prestigious Trail Rated badge.

Others are traction, articulation and maneuverability. Jeep jealously guards the thresholds for these tests, developed in conjunction with the Nevada Automotive Test Center.

Except for the Compass, every vehicle in the Jeep showroom has a Trail Rated variant. The Patriot is the first product based on a front-wheel-drive platform to earn this distinction.

Matt Liddane, Patriot chief engineer, says the vehicle was designed from the ground up to be Trail Rated. But creative solutions were required to resolve unforeseen problems that arose during development.

“The skid plate didn’t start off that thick,” Liddane says, referring to the 0.12-in. (3.1-mm) shield under the engine. Rear-mounted shields of the same thickness protect the transaxle and fuel tank.

Trail-Rated Jeep Patriot's CVT has 19:1 crawl ratio.

Other content not found on the Compass and non-Trail Rated Patriot models include the CVT2L continuously variable transmission with a 19:1 crawl ratio. The CVT2 features a maximum low-gear ratio of 14:1.

A heavy-duty cooling system and high-mounted rear-differential vent also ensure the Trail Rated Patriot performs up to par.

“The lateral link in the suspension didn’t have the structural member tying it together before,” Liddane says. “All that was added during development.”

Sources tell Ward’s the water-fording test proved most difficult for the Patriot, which also shares its platform with the Dodge Caliber small car.

Extra mastic is used in Patriot’s door seals and particular attention was paid to the application of sealer on the body-side outer and inner. But Liddane says water-fording proved no more difficult than any other challenge, adding thermal concerns also were high on his to-do list.

The heavy-duty cooling module on the Trail Rated Patriot is designed to handle the increased performance that off-roading will demand of its 2.4L I-4, the largest of Chrysler’s World Engine family.

“If it gets hot, you don’t want to find yourself saying, ‘I don’t have the power,’” Liddane says.

Development of the Trail Rated Patriot included testing in rugged Moab, UT. However, there are no plans to try the vehicle on California’s storied Rubicon Trail.

“There’s no need,” Liddane says, adding the Trail Rated badge denotes a minimum standard. Similarly capable Jeeps from the top-end Commander to the down-market Liberty offer degrees of performance above the minimum.

“This Jeep is all Jeep,” Larry Lyons, vice president-FWD product team, says.

Jeep expects the take rate for the Trail Rated Patriot, which features the most robust of two available 4-wheel-drive systems known as Freedom Drive II, will be about 10%. The starting price is $19,175, while the base Patriot stickers for $14,985.

Jeep claims the Patriot will offer the best off-road capability in its class, which includes competitive vehicles such as the Ford Escape, Toyota RAV4 and Honda CR-V.

Jeep also is best-in-class in fuel economy. The optional 172-hp 2.4L I-4 and the 2.0L I-4 World Engine both are expected to achieve 30 mpg (7.8 L/100 km) on the highway.

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