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The Jeep Cherokee will be available with engine start-stop technology later this year, as Chrysler Group LLC continues to use that vehicle as a springboard for launching new technologies.
Start-stop systems automatically turn off the engine when a vehicle comes to a stop. The system seamlessly restarts the engine when the driver steps back on the accelerator.
Some Ram 1500s have been equipped with start-stop since the 2013 model year, but the 2015 Cherokee will be the company‘s first widespread application.
“The Cherokee is a very important play for introduction of technology in the company, and also due to the large volumes, it’s where we can get the most benefit for the largest number of customers,” said Brad Pugh, the vehicle’s chief engineer.
The Toledo-built Cherokee was the first vehicle to get Chrysler Group’s nine-speed automatic transmission, as well as the first to use the company’s new “rear-axle disconnect” that improves fuel economy in four-wheel drive vehicles.
Those innovations are starting to spread to other Chrysler vehicles.
The new Chrysler 200 will make use of the nine-speed transmission and the rear-axle disconnect. The upcoming Jeep Renegade will also use the rear-axle disconnect.
Even when they aren’t engaged, four-wheel drive and all-wheel drive systems have moving parts that reduce a vehicle’s fuel economy. By disconnecting the rear axles from the rest of the powertrain, Chrysler can keep those losses to a minimum.
Mr. Pugh called the engineering on that system a “marvel.”
Zoran Filipi, a professor at Clemson University’s International Center for Automotive Research, said Chrysler’s approach is an innovative solution to a well-known problem. He said it’s the kind of development the industry is likely to see more of as the new government fuel economy standards approach.
“This fits very well into the current trend in the automotive industry, where everybody's working feverishly to develop new technologies that will allow reaching these very ambitious goals for the 2025 CAFE [standards] and every percent counts,” Mr. Filipi said.
Mr. Pugh said Chrysler estimates the rear-axle disconnect improves fuel efficiency by 2.5 to 3 percent. Results from EPA testing aren’t back yet, but stop-start is expected to boost city fuel economy by up to 3 percent.
Those are small but not insignificant amounts as automakers chase government benchmarks and drivers contend with fuel prices that are averaging almost $3.70 a gallon nationally.
In the Cherokee, start-stop technology will be standard with the 3.2-liter V-6 engine. It won’t be offered on the four-cylinder version. Chrysler said the system will be available starting in the year’s third quarter.
The new Chrysler 200 will get start-stop in the year’s fourth quarter.
Start-stop is no longer cutting-edge stuff, but officials say it’s still not widespread enough to be considered common. In order to ease buyers into how the system works and what they can expect, each new car equipped with it will come with an information card.
“We feel once the customer has understood it, and had some time in it, the benefits far outweigh the unknown,” Mr. Pugh said
The company will swap out the standard starter in favor of quicker and more durable starter that can handle the increased workload and provide seamless restarts.
Chrysler said start-stop cycles won’t affect power windows, heating and cooling, or multimedia.