Western Star goes aerodynamic

Nov. 1, 2014
NTEA Truck Product Conference 2014 report

WESTERN Star’s 245 dealers began taking orders for the new 5700XE in the fall and production at Daimler Trucks North America’s truck plant in Cleveland, North Carolina, is scheduled to begin in March or April.

Western Star is best known for its vocational and heavy-haul Class 8 models, but it is expanding into the aerodynamic on-highway market with this all-new model, which combines the fuel efficiency of an aerodynamic package and optimized drivetrain with styling that echoes the brand’s more traditional image.

With less than 3% US/Canadian market share in Class 8, Western Star is a relatively small truck maker, but as part of DTNA, it had access to its parent company’s advance powertrains and aerodynamic expertise in developing the new model. 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.

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 lb-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 an expected fuel-efficiency improvement of up to 15% over Western Star’s current on-highway 4900FE model.

The DT12 is a fully automated manual transmission featuring high-speed, computer-controlled shift and clutch actuators that automatically and seamlessly select the right shift pattern and perfect clutch engagement for fuel economy and driving conditions. 

The 12-speed DT12 is available

in direct or over-drive top gear configurations. 

Other features—such as Creep Mode, which simulates a torque converter to improve low speed maneuverability; Skip Shift, which automatically skips gears to achieve cruising speed sooner; and eCoast, which enables vehicles to coast when the requested speed can be achieved or maintained with the engine operating at idle speeds while preserving momentum—will further maximize fuel efficiency and performance of the 5700XE.

Based on the steel cab used by Western Star’s vocational models, the 5700 will be available with sleepers ranging in size from 34 to 82 inches. A day cab model will also be offered.

The Daimler Airlink air suspension will be standard on all 5700 models. Electronic controls for improved traction performance will be fitted to highly fuel-efficient 6x2 models.

Additional features include:

  • Meritor WABCO OnLane Lane Departure Warning System: Audible, directional warning signals let the driver know if the truck’s course needs to be corrected. 
  • Meritor WABCO OnGuard Adaptive Cruise Control: Using on-board sensors and working with conventional cruise control, the 5700XE will automatically adjust vehicle speed to maintain the set cruise speed and a safe distance from vehicles in front of it.  
  • Meritor WABCO OnGuard Collision Mitigation System: This radar-based system provides visual and audible driver alerts through an in-cab dash display when the vehicle’s following distance could result in a rear-end collision. If the driver doesn’t take action, OnGuard’s Active Braking automatically de-throttles the engine and activates the service brakes. 
  • Intelligent Powertrain Management (IPM): A feature of the DT12 transmission, IPM uses GPS and pre-loaded terrain maps to evaluate the road profile up to three miles in advance and determine the most fuel efficient vehicle operation (including vehicle speed, transmission gear, and engine rpm). 
  • ABS brakes with electronic stability and roll stability control: Working together, the 5700XE’s ABS with electronic stability and roll stability control stabilize the truck, and can help reduce roll-overs, skidding and spinouts. 

For vocational applications, the 4700 is the company’s newest truck.  John Tomlinson, heavy vocational sales for North America, provided an update on new features that are being offered:

  • New suspension and lift axle choices are being offered from Neway ADZ, and Hendrickson.
  • New air tank featuring three chambers will be offered.  The triple-chamber tank combines air capacity into one tank for cleaner chassis and less routing. 
  • Electronic stability control will be available on the 4700, 4800, and 4900 models.

Tomlinson also showed a new dash mount device prep feature designed to speed upfitter installation of navigation systems, cameras, and other dash-mounted equipment. With three pre-drilled mounting holes and a center hole to accommodate wiring, the feature takes time out of the installation without adding liability to the upfitter. ♦

About the Author

Rick Weber | Associate Editor

Rick Weber has been an associate editor for Trailer/Body Builders since February 2000. A national award-winning sportswriter, he covered the Miami Dolphins for the Fort Myers News-Press following service with publications in California and Australia. He is a graduate of Penn State University.