LAS VEGAS. Best known for its vocational and heavy-haul Class 8 models, Western Star Trucks is expanding into the aerodynamic on-highway market with an all-new model. Shown publically for the first time at a press conference here, the Western Star 5700XE combines the fuel efficency of an aerodynamic package and optimized drivetrain with styling that echoes the brand's more traditional image, according to the company.
With less than 3% U.S./Canadian market share in Class 8, Western Star is a relatively small truck maker, but as part of Daimler Trucks North America, it had access to its parent company's advance powertrains and aerodynamic expertise in developing the new model, according to general manager Michael Jackson. The result is a new tractor with styling quite distinct from other aerodynamic trucks on the market combined with the most efficient integrated Daimler powertrain technologies, he said.
Daimler's Detroit will supply the 5700XE's three engine displacement choices -- the DD13, DD15 and DD16 with ratings up to 600 hp. The standard transmission for all three engines will be the Detroit DT12 automated manual transmission, although buyers will be able to spec an Eaton manual transmission as an option. The 5700's standard axles will also be supplied by Detroit, although Meritor drive axles will be available as options, and the only suspension offered will be Daimler's Airliner air suspension.
The new 5700's most fuel-efficient powertrain will combine a new version of the DD15 that generates 400 hp and 1750 lbs. ft. peak torque at 1300 rpm. Combined with a specially calibrated DT12 transmission and final gear ratios of 2.41 for a 6x4 Detroit rear axle or 2.28 for a 6x2, that highly integrated powertrain will deliver up to a 15% fuel efficiency improvement over Western Start's current on-highway 4900FE model, according to Brad Williamson, DTNA's manager of engine and component marketing.
Williamson added that starting in 2015 all DT12 transmission will have a new intelligent powertrain management system that uses 3D mapping and GPS to look up to three miles down the road so it can automatically adjust engine and brake performance to maximize fuel efficiency.
Characterizing the 5700's styling as "edgy," Western Star dir. of marketing Ann Demitruk said that design elements like sharp edges along its fenders and bumper endcap "fangs" not only provided its distinctive look, but also added to the new truck's overall aerodynamics.
"The rounded aero look didn't fit Western Star's iconic look," said senor designer Don Vena. His team retained the brand's traditional "motorcycle fenders," but added angles and edges to better manage airflow. Similarly they kept the traditional rectangular headlight shape, but fitted them with projector lamps and LEDs for improved visibility.
While the design team brought in customers to critique their ideas, the engineering team refined them in DTNA's full-sized wind tunnel, according to Jesus Gomez, dir. of engineering. Looking at wind coming from a wide range of angles, the design and engineering teams achieved an average 12% reduction in drag compared to the 4900FE, he said.
Western Star's 245 dealers will begin taking orders for the new 5700XE in the Fall. Production at DTNA's Cleveland, NC, truck plant is schedule to begin next March or April, according to Jackson.
