Technology Breakdown: Western Star 49X

Western Star Builds Next-Generation Vocational Truck

It’s fairly rare to witness a completely new truck in the Class 8 market, especially one dedicated to the vocational segment. That is precisely why it took many by surprise when Western Star teased dealers with a prototype in February.

“This is the culmination of nearly 6 years of work engaging thousands of people within Daimler Trucks North America on this project,” says David Carson, the company’s Senior Vice President, Vocational Segment. “We believe that we’re launching the best tool in the vocational space—the most tested, safest, most advanced vocational truck.”

The Western Star 49X is designed to deliver maximum versatility in a pur-

The optional three-piece rear window is 77% larger than that of the Western Star 4900.

The 49X was designed from the ground up to meet the most demanding vocational applications.

by Curt Bennink

ALL PHOTOS COURTESY OF DAIMLER TRUCKS NORTH AMERICA

pose-built package. It features a stronger, lighter chassis that is equipped with the company’s new X-series cab. It enables a total weight savings of over 350 lbs. (159 kg) in like-for-like spec’ing versus the current Western Star 4900, which is currently slated to remain in production.

The weight savings starts with a new vocational frame. Single-channel frame rail options are available in a variety of thicknesses and feature ratings up to 3.7 million RBMs (Resisting Bending Moments). This yields greater durability and significant weight savings for greater capability and payload.

“The beauty of that single frame rail is obviously you can save a lot of weight without sacrificing the RBM, the resistance to bending,” says Samantha Parlier, Vice President of Vocational Market Development.

For customers that need maximum frame strength, frame inserts are available. “One thing that is unique about Western Star inserts is we do seal them,” says Parlier. Vocational trucks can accumulate magnesium chloride, mud or even water between the rails. “Our rails are actually sealed so that doesn’t happen.”

C-channel frame reinforcements are available with RBMs up to 5.4 million. Multiple parent rail front frame extension options are available for applications requiring front-mounted equipment, such as a plow.

The frame rails are kept clear to ease upfits. Clear back-of-cab packaging allows for easier upfit with features that include: forward-mounted DEF tanks; standard in-cab battery box; multiple air tank mounting locations; air dryer mounted underhood (set-back axle) or under cab (set-forward axle); optimized fuel tank sizes; a compact Detroit aftertreatment system; and functional dual vertical exhaust stacks.

The 49X will also accommodate a full array of rear suspension options. “Pretty much if you have heard of it in the vocational market, we’re offering it on this new product,” says Parlier.

Purpose-built cab

Western Star designed a new purpose-built cab for the 49X. “If we’re going to change the cab in terms of comfort, quietness and safety, it really requires us to transition from what we have been doing into new and more creative ways to provide that comfort

for the operator,” says Carson. typical coil-over shock suspension on. You end up with drivers that are

“We use topology optimization, system with spring and damper. The happier at the end of the day and which is software technology,” explains system isolates, absorbs and dissipates more energized.” Parlier. “We were able to take an alu- vibrations from the chassis when drivminum cab and strategically reinforce ing over uneven terrain to protect the Detroit debuts vocational series it with steel to make it as tough, if not hood from damage and cracking. automated transmission tougher, than the current cab. It was an The ISO Tech Hood Suspension is a The Detroit DT12 transmission has engineering exercise. The cab is an area first for the vocational truck industry. been redesigned for vocational where we really pulled out all of the “You’ve never seen a hood in a voca- applications. tools in the toolbox and centered that tional market that has a suspension sys- “It was about a $100 million investtopology optimization around how ex- tem,” says Parlier. “As the frame moves, ment in creating a vocational transmisactly we create an exoskeleton to keep it completely isolates the hood from sion,” says Carson. “It has been tested operators safe.” for over 35 million

Western Star claims global miles. They are the X-series cab is the new transmissions largest in the segment in the same family of with 10-13% greater the DT12, but it’s not space than com- simply just a modified petitive cabs. It was transmission.” designed specifically Power is transfor vocational appli- mitted from either cations and provides a Detroit DD15 Gen additional vehicle 5 or DD16 engine weight savings while through the new delivering long-term DT12 Vocational durability and opera- series of automated tor comfort. Advanced manual transmissions. topology was utilized These transmissions to ensure rigidity and are available as the strength and deter- DT12-V or DT12-VX mine where more and are rated up to material was needed a Gross Combined in the steel-reinforced Weight Rating (GCWR) aluminum cab. of 330,000 lbs.

Development work (149,685.5 kg). Both on the cab was the transmissions include most extensive in the The new hood uses a patented ISO Tech Hood Suspension system that PTO capabilities company’s history and behaves similarly to a typical coil-over shock suspension system with that allow for added included multiple cab spring and damper. The system isolates, absorbs and dissipates vibrations flexibility. “It has the crush tests to ensure from the chassis when driving over uneven terrain to protect the hood from damage and cracking. eight-bolt left hand cab integrity in case of side PTO,” says Parlier. a rollover. Full-vehicle It also has a rear PTO. shaker tests replicated 800,000 mi. the frame in terms of force and inputs.” Unique work application modes and (1,287,475.2 km) of use to test the cab This allows a weight reduction. “We shift map strategies are available for mount system, which uses vocational didn’t need all of those reinforcements all types of terrain. A Rock-Free Mode cab isolators mounted outboard for in the mounting area and stress points allows the 49X to free itself from wheel optimal stability and reduced fatigue that you typically see because we have stuck situations. An Off-Road Mode to both the operator and the cab. the suspension protecting the hood.” enables smooth driving on extreme

The hood of the 49X is constructed An unexpected benefit is reduced terrain such as logging roads and of high-strength, lightweight, mold- driver fatigue. “When driving the truck, rock quarries. Power Launch provides ed composite for impact resistance you see a lot less movement at the powerful takeoffs while protecting the and durability. The new hood uses a corners of the cab, which is right by clutch and driveline. patented ISO Tech Hood Suspension the dash,” says Parlier. “So, their brains The transmission also offers a system that behaves similarly to a aren’t trying to figure out what’s going neutral feature for paving applications

TOP TO BOTTOM: ABA5 detects distance and speed of moving and stationary objects in the driving path of the 49X and determines if warning or automated braking is necessary.

Side Guard Assist uses radar technology to detect moving objects and pedestrians on the passenger side of the truck.

The Western Star 49X features a stronger, lighter chassis that is equipped with the company’s new X-series cab. It enables a total weight savings of over 350 lbs. in likefor-like spec’ing versus the current Western Star 4900.

that allows the truck to be pushed by the paver. “You don’t have to stop,” says Parlier. “You can just drive away.”

For customers who already have a powertrain preference, there are other options. “We still provide choices,” notes Parlier.

Safety is a priority

The 49X is equipped with the Detroit Assurance suite of safety systems, which includes an advanced collision mitigation system. The Detroit Assurance system on the 49X off ers Side Guard Assist (SGA), Active Brake Assist 5 (ABA5), tailgate warning, Adaptive Cruise Control (ACC) to 0 mph, lane departure warning, video capture, intelligent high-beam and automatic wipers/headlamps.

With optional SGA, radar technology detects moving objects and pedestrians on the passenger side of the 49X that may otherwise fall in the operator’s blind spot and alerts them with both auditory and visual warnings for safety on the jobsite or on the way there.

ABA5 detects distance and speed to moving and stationary objects in the driving path of the 49X and determines if warning or automated braking is necessary. The system works down to 5 mph (8.0 kph), making it optimal for busy jobsites and in congested urban areas. It also recognizes moving pedestrians who are crossing in the truck’s path, alerting and applying the brakes if the operator does not react.

Slips, trips and falls rank second among the most common types of workplace injuries. In certain applications, such as concrete ready-mix trucks, the operator may enter and exit the cab up to 50 times during a shift. In these applications, ingress and egress are real concerns.

“The real stars of every jobsite are the men and women working at it, which is why the Western Star 49X was engineered to deliver best-inclass safety with easier entry and exit to reduce workplace injury, and best-in-class visibility to benefi t not

only the operator but the entire crew,” Carson states.

Door opening angles of 70 degrees, fi ve hand holds and step treads widened by half an inch and constructed as a staircase help facilitate safer entry and exit from the cab. The steps start closer to the ground and use a volcano tread for confi dent footholds with high traction, added toe clearance and mud, dirt and debris pass through.

Enhanced visibility comes from a sloped hood enabled by splayed frame rails; a lowered engine position and underhood engine air fi ltration; a 28% larger, single-piece, roped-in windshield; and a rear window that is 77% larger versus the 4900. Optional Borofl oat glass in the front windshield and optional poly carbonate in the rear windows provide impact resistance from debris.

The mirrors have also been improved to increase visibility in demanding applications. A C-bar mirror system features door-mounted mirrors that mitigate the eff ects of chassis and engine vibration to keep them stable and usable in off -road or paving applications where visibility by the operator to the crew at the back of the truck is critical.

A dual-stage LED headlight system features an internally printed heat grid and ambient air temperature sensor that can melt 3 mm (0.12 in.) of ice in less than 10 minutes at -40 F (-40 C) or burn through condensation in warm, humid environments. Combined with a 45-degree light pattern, the headlight system provides smooth, uniform illumination to improve visibility and safety.

Interior places technology within easy reach

In all models, a wraparound dash puts the driver command center and b-panel in the operator’s line of sight. On the b-panel, a fl ex panel houses tablet prep or can be confi gured for an additional 12 switches or 10 gauges. Along with QuickFit Dash Access designed for seamless telematics or other device integration, equipment control and device access is placed within easy reach for the operator.

Much attention has been spent on even the most minute details. “Our bottom-line intent was to deliver a truck that benefi ts our customers’ bottom lines,” says Carson. “We know the conditions our customers are working in. We know the challenges of their operations and we know that productivity at the site

Power is transmitted from either a Detroit DD15 Gen 5 or Detroit DD16 engine through the Detroit DT12 Vocational series of automated manual transmissions which are rated up to a GCWR of 330,000 lbs.

matters most. That’s why the all-new 49X is purpose built for durability, safety and maximum uptime—and for our customers.”

The 49X is available for ordering this winter and fi rst deliveries begin in early 2021. |

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