Volvo touts I-Shift role in fuel economy boost

Saying it already is delivering up to an 8 percent fuel efficiency improvement over U.S. Environmental Protection Agency 2007 engines, Volvo Trucks on Wednesday, Sept. 21, announced a powertrain package for its VN series tractors aimed at reducing fuel consumption. The new XE13 – exceptional efficiency – powertrain package lowers engine rpm at a given vehicle speed, a concept Volvo calls “downspeeding.” Possible through the combination of Volvo’s I-Shift automated manual transmission and a Volvo engine with modified software, XE13 allows the engine to cruise at just 1,150 rpm at 65 mph – about 200 rpm less than the average truck sold today.

“Historically, we’ve seen a slow progression toward a lower ‘sweet spot,’ with the 1,300 to 1,500 rpm range as the current industry standard,” says Ed Saxman, Volvo Trucks product manager – powertrain. “The engine with the XE13 package has a ‘sweet spot’ of 1,050 to 1,500 rpm. Customers gain about a 1.5 percent fuel efficiency improvement for every 100 rpm of ‘downspeeding,’ so fleets that spec XE13 can expect up to a 3 percent improvement when compared to another overdrive transmission in a similar operation.”

The XE13 package is rated up to 80,000 pounds GCWR and includes the following components:

Volvo D13 engine with 425 hp and 1,750 lb-ft of torque
Volvo I-Shift overdrive transmission with a 0.78:1 ratio
Axle ratios of 2.64 to 2.69

Proprietary software that facilitates seamless communication between Volvo’s integrated powertrain components.

“With the new package, the engine runs in its sweet spot at any given speed, never straying from its sweet spot at any point from zero through top speed,” Saxman says. “When cruising at speeds below 60 mph, the intelligent software is designed to prompt the I-Shift transmission to downshift only when necessary for maximum fuel efficiency. Like the song says, the I-Shift software knows when to hold ’em and knows when to fold ’em.”

“Any fleet focused on spec’ing their trucks for maximum fuel efficiency can benefit from the XE13 package, but fleets spending considerable time cruising at highway speeds will see the greatest improvements,” says Ron Huibers, Volvo Trucks senior vice president of sales and marketing. “Our intelligent, integrated XE13 package delivers improved fuel efficiency without sacrificing drivability during steep mountain inclines or stop-and-go traffic.”

The XE13 powertain package is the latest step in fuel efficiency for Volvo customers. In November 2009, the launch of Volvo’s EPA ’10 certified No Regen engines with SCR technology gave customers a 5 percent boost. Volvo’s powertrain enhancements and advanced aerodynamics announced earlier this year deliver up to an additional 3 percent.