Next-generation Wrangler will get an aluminum body

TOLEDO, Ohio -- The next-generation Jeep Wrangler will feature an aluminum body to save weight, and will remain a body-on-frame vehicle, sources say.

Because Chrysler won't make the switch to unibody construction, Wrangler assembly will probably stay in Toledo. And that means the company will likely produce more Wranglers for U.S. dealers and for export.

There's plenty, though, that we don't know about the redesigned SUV, due in 2017:

• Will Chrysler downsize the current 3.6-liter V-6 and squeeze in an eight-speed automatic transmission? 
• The Wrangler will keep its frame, but will the next-generation retain its solid axles, preferred by off-road enthusiasts? With its recent one-off concept vehicles, the company has dropped various hints about the nature of the redesigned SUV. 
• The city of Toledo on Tues., Oct. 21, agreed to buy 32 acres adjacent to the Wrangler assembly plant. That suggests that a plant expansion is in the works, but the city and the automaker are mum on the possibility. 

The Wrangler tale started in early October in Paris when Sergio Marchionne, CEO of Fiat Chrysler Automobiles, was asked about two of his previous promises -- never to build Wranglers outside Toledo and no more brick-and-mortar factories in North America.

In his response, Marchionne chose his words carefully. He said that the next Wrangler needed to lose weight and that doing so with aluminum might mean the Wrangler had to move elsewhere because of excessive costs to re-equip the Toledo plant for aluminum assembly.

He pointed out that Chrysler had excess capacity in at least two of its existing plants. But the two plants he named currently build only unibody vehicles, which can't be built on the same line as body-on-frame vehicles.

Marchionne's comments set Toledo on edge and started a campaign to keep the Wrangler in its historic home. But now that sources have confirmed that the vehicle will remain body-on-frame, Toledo is breathing a little easier.

Toledo Assembly is one of only two Chrysler body-on-frame assembly plants in the United States. And the land purchase next to the plant suggests both that an expansion is possible and that local officials are working on it.

An expansion could keep Wrangler production flowing and avoid a profit-eroding production hiatus like the one the company endured in 2012 and 2013 when it retooled the unibody half of Toledo Assembly for the Jeep Cherokee.

Enthusiasts and others, though, are just as eager to know how the redesigned SUV will be equipped.

Jeep won't talk about its plans for the next-generation Wrangler other than to say it "will be the most capable Wrangler ever."

Yet engineers and designers with the brand have provided regular clues to what they were working on with experimental vehicles taken out to the annual Easter Jeep Safari in Moab, Utah.

In 2011, for example, Jeep produced a one-off Wrangler it called Pork Chop. The concept dropped various components and replaced others with aluminum, carbon fiber-reinforced plastic and other lightweight materials to shed 850 pounds from the 3,839-pound base 2011 Wrangler Sport.

Two years later, Jeep's design team followed up with another one-off project for Moab that it called Stitch. Based on a heavy-duty Wrangler Rubicon, Stitch shaved weight wherever possible, including its frame, axles, body and interior.

The exercise shed more than 1,130 pounds from the 4,132-pound base 2013 Rubicon.

But weight is not the only factor that keeps the hot-selling Wrangler from improving its fuel economy. Aerodynamics and the drivetrain are likely to play an even larger role than aluminum in boosting the redesigned SUV's mileage.

Aerodynamically, the Wrangler is often called a rolling brick because of its flat front surfaces that block air.

A more angled front grille would better slice the air instead of hitting it with the equivalent of a flat board, while a raked windscreen would reduce drag substantially as well.

Marchionne said Jeep also needs to find a way to use smaller displacement engines in the Wrangler than the current 3.6-liter V-6.

Also, more gears in the automatic transmission than the current five-speed would significantly boost mileage.

The eight-speed automatic that the automaker uses in its rear-wheel-drive lineup doesn't fit in the current Wrangler. That transmission helps the Ram 1500 achieve the highest highway fuel economy rating of any full-size pickup and would dramatically improve the Wrangler's fuel economy as well.

Marchionne and Jeep brand head Mike Manley have repeatedly said that the company has two overwhelming priorities as it redesigns the Wrangler for 2017: keep Wranglers flowing off the assembly line uninterrupted and don't screw up a good product.

"It is a problem because the evolution of the architecture will entail a significant change in the way in which Wrangler is built," Marchionne said in Paris. "We need to preserve two things: all of [Wrangler's] capabilities, and certainly we need to modernize it."

The likely plant expansion would keep Wrangler production flowing. And the body-on-frame is a good start to keep the SUV's capabilities. The company has hinted how it will modernize the next Wrangler, but the details are yet to come.