Western Star adapted a cap suspension systemWestern Star, owned by Daimler, has adapted a cab suspension system designed by Mercedes Benz in Europe. The cab suspension mitigates rear protrusion and provides large open space for rear engine PTOs.

THE Western Star 4700, a Class 8 vocational truck, is the first new commercial offering from the Daimler-owned company in over a decade, with targeted delivery in early 2012.

It's designed for crane, mixer, roll-off, and dump markets. There is smaller powertrain availability with the introduction of ISC/ISL and DD13 engines.

It has a splayed frame rail with front-frame extensions. The common Daimler chassis platform uses a 33.6-inch constant inside frame dimension on a 50mm grid.

“The first three weeks this was out, we sold out first-quarter production, so that was pretty good success,” Dan Silbernagel said. “People were clamoring for it. Our dealers want to get this truck on the ground.”

He said 167 inches is the shortest wheelbase offered.

Dan Silbernagel of Western Star “You can keep all air tanks inside the rail,” he said. “You don't have to do any perpendicular outside. Exhaust is 6.25 inches back of cab. On the passenger side, the exhaust pipe below the rail for DD13 goes 12 inches back of cab.

“All air tanks are inside the rail. Perpendicular tanks forward of ATS are only with ISC/ISL.

“On the set forward, we moved the axle 18 inches forward. So a six-gallon DEF tank and 80-gallon, 25-inch-diameter fuel tank provides zero back of cab protrusion. The exhaust system is still the same.”

For underbody plows, Western Star uses 60- or 90-gallon shallow rectangular fuel tanks. The 60-gallon tank protrudes 30.6 inches, the 90-gallon tank 52.2". Axle-suspension and tire-size requirements will be imposed in order to achieve 21-inch ground clearance.

“The rear cab suspension has a crossmember-less rear mounting system with an air-over-shock design, so there are shocks inside air bags,” he said. “That helps mitigate back-of-cab protrusion from putting external shocks back of cab. This actual system came from Mercedes Benz in Europe. We were able to take that and not have to redesign an entire new system. It allows a huge area of open space for rear-engine PTOs. The crossmember is moved out a little to maintain integrity in the high-stress area.”

He said Western Star wanted to make electrical integration from the truck to body more user-friendly, so it created a dedicated raceway to route all wiring for body installation.

“So every connection you use for body setup will be in-cab,” he said. “It fits 6.5-inch bundles, and there's a 4x4 pass-though in the cab floor. What's good about this is that you will have all information about what the pass-through point is, and you can create your own plate and secure your harnesses to that and just feed up into the cab, take four bolts and bolt it right in there. You don't have to feed wires through roof panels or anything like that.

“We added a power distribution module (PDM) in there. For high-amp requirements, it separates body electronics or truck electronics so if something catastrophic happens on either end, it doesn't take down the entire product. This also allows 200 amps, and you still have in reserve in the main module an additional 80 amps of power.”

Western Star designed the cab with galvannealed steel, and it is precision-welded, then dipped in a proprietary 17-stage e-coat process for long-lasting protection against corrosion.

The new 4700 will be built alongside all of Western Star's other models in Portland at a former Freightliner plant now completely dedicated to Western Star. Along with its own plant, Western Star was also assigned dedicated management, engineering, and marketing teams.

Western Star now offers two new suspension options for its various truck models and configurations.

The first — a Neway 60,000-pound capacity AD 260 Tandem air suspension system — is available for all Western Star truck models utilizing Dana D60-190 axles, and contributes to the vehicles' road-holding and handling and positive axle alignment, virtually eliminating tire hop and providing superior traction. The highest capacity air suspension in the industry, the Neway system also provides predictable roll stiffness for high center of gravity loads — particularly important for front and rear discharge mixers.

In addition to the Neway system, the 40,000-pound TufTrac All Wheel Drive (AWD) high-performance vocational suspension is also available as an option for the Western Star 4800 with 40,000-pound axles. Specifically designed for on- and off-road high articulation operations where it's important to navigate bumps, ridges, and washboard without bottoming out, the 40,000-pound TufTrac mounting is a lighter, more affordable alternative than the 46,000-pound option.

Additional benefits of the 40,000-pound TufTrac include a uniform load over each wheel, maximum traction, and a smooth and quiet ride.

Both the Neway AD 260 Tandem and 40,000-pound TufTrac suspensions are now available to order.

Western Star also has introduced a new auto hauler based on the 4900 model, with a chassis re-engineered to accommodate EPA 2010 engines and aftertreatment systems. It will be offered in both a 123- and 132-inch BBC configuration.

Specialized front and rear suspensions combined with a lower cab mounting system will provide a 101.4-inch cab-to-ground height without third-party modifications to the cab roof. Standard power for the auto hauler will be the Cummins ISX15 engine with selective catalytic reduction (SCR) emissions technology and power ratings that range from 400 to 600 hp and up to 2,050 ft-lbs of torque.

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