What’s New in Construction Trucks

As construction truck builders rang in the New Year, they had plenty of improvements—including some all-new models—to showcase in 2007. At World of Concrete 2007, International introduced a new truck, the 5900 Paystar set-back axle model. In 2006, Volvo brought forth a new family of engines, including one for construction trucks, and a new automated transmission. As well, Mack, Freightliner, Sterling, Peterbilt, Western Star, and Kenworth all announced improvements.

A number of changes centered on meeting EPA ’07 exhaust emission requirements. Except for Caterpillar, virtually all engine builders use exhaust gas recirculation (EGR) systems to comply. Caterpillar invented its ACERT system, which relies on multiple fuel injections in the cylinder to lower the fuel-burn temperature. EGR systems require extra cooling capacity in the radiators, and truck manufacturers have figured various ways to accommodate these larger radiators. In addition, the new after-treatment devices, which look like mufflers, are mounted in various locations to avoid conflicts with the truck body.

New Equipment
“We put the radiator on top of the frame rails and put a new hood on the chassis for our WorkStar model,” says Phil Christman, vice president and general manager at International’s Severe Service Vehicle Center. “We didn’t cut the frame rails to fit the new radiator. You need full frame rails for mounting a snowplow. And we kept the front-mounted power take-off [PTO]. For a mixer you need to drive the barrel with the front PTO in some cases.” International’s WorkStar model won the JD Power Award for Vocational Trucks in 2006, Christman says.

International’s Paystar 5900 set-back axle truck completes the Paystar lineup, which includes the 5500 and 5600 Series trucks. The 5900 will accommodate 13- and 15-liter engines, Christman says. And now International is offering the Cummins ISL engine, which can range up to 350 horsepower (hp), in the 5500 and 5600 Series trucks. “That can save you 500 or 600 pounds over a big-bore engine,” says Christman. “This will be good for mixer or dump truck applications. For shorter distance hauling the ISL is fine, but it won’t handle the constant pounding of long-haul trucking that a bigger-bore engine can take on.”

Volvo’s New Family
Volvo last year brought out a new family of heavy-duty diesel engines, including the 13-liter D13, which fits into the VHD vocational truck and tractor. The D13 is available with horsepower ratings from 335 to 485 and torque levels from 1,350 to 1,650 foot-pounds.

Significant features of the new Volvo engines include:

• Fuel injection pressures that are 20% higher than in the Volvo D12. The higher fuel pressures improve fuel atomization and dispersal in the cylinder for more efficient combustion and lowered emissions.
• Multiple fuel injections per stroke. The engines use a new proprietary actuation strategy for the dual-solenoid unit fuel injector that Volvo introduced on the D12. The result is precise control over fuel injection for emissions control and engine performance.
• A single-stage variable-geometry turbocharger, with a sliding nozzle and electronic actuation. The new turbo delivers improved engine response, Volvo says, as well as greater backpressure for the EGR system. And the electronic actuator gives more precise control than a pneumatic actuator.
• Increased peak cylinder pressures allow the engine to extract more energy from each drop of fuel.
• A single-piece, rigid deck cylinder head with four valves per cylinder is built to withstand the higher injection and cylinder pressures for increased durability and reliability.

Last September, Volvo introduced its I-Shift automated transmission for model year 2008 trucks. The I-Shift can be ordered for delivery in the second quarter of 2007. Three I-Shift models will be available, including one for the Volvo VHD construction truck. Some 19,000 I-Shifts were sold in Europe in the first six months of 2006.

The Volvo I-Shift is a 12-speed, single countershaft transmission built up with a splitter and a main section with three forward and one reverse gear, plus a range gear. It is an automated mechanical transmission and does not use synchronizers in its main section. The I-Shift is a “two-pedal” transmission and does not require a clutch pedal. Transmission controls are located on a compact control console and lever attached to the driver’s seat.

Ergonomics From Mack
Mack has introduced several ergonomic improvements on its Granite models, all aimed at making the driver more comfortable. According to Stephen Ginter, Mack vocational product manager, those improvements include:

• A cab that is 4 inches deeper to add belly room and enhance the driver’s position
• An infinitely adjustable steering column that tilts up and down and telescopes in and out to fit virtually all drivers
• An air-assist clutch that reduces clutch travel by 30% and cuts clutch effort by 25%
• A new, interior lighting system that features a driver’s task light, a map light for the passenger, as well as two general overhead lights
• Three new overhead storage compartments can store papers and gear; the center compartment can carry the driver’s CB radio.

Mack’s two new engines are the MP7 and the MP8. The MP7 ranges up to 405 hp in an 11-liter block; the MP8 is a 13-liter engine that can pump out up to 485 hp. Both engines feature high-performance cooled EGR for emissions control, a variable geometry turbocharger, electronically controlled unit fuel injectors, and wet sleeve cylinders with single-piece steel pistons.

New From Peterbilt
Peterbilt’s all-new product lineup introduced in 2006 includes two new vocational vehicles, the Model 367 and Model 365, which are now in production. Both new models are available in truck and tractor configurations and with set-back and set-forward front axles, says Al Zwicky, senior applications engineer at Peterbilt. The bumper-to-back-of-cab dimension is the primary difference between the two: The Model 367 is 8 inches longer than its brother and will accommodate a larger engine.

Peterbilt also introduced a Model 367 Heavy Haul tractor, which has a slightly different hood design to provide for a larger, high-capacity cooling package.

On the Model 365, Peterbilt moved the axle back compared to its predecessor, the Model 357, to provide more front-end weight distribution. Steering geometry was changed to provide better maneuverability. Headlamps were improved for better forward lighting.

Peterbilt’s 2007 version of trucks will have diagnostic text messaging available on the dash to provide news of what’s wrong with your truck. “You won’t need a cross reference to tell what’s wrong,” says Ken Marko, manager of market planning and research.

Axle weight ratings were not changed from the 357. Engine options for the Model 365 include the Caterpillar C9 and C13 and the Cummins ISM and ISL, with horsepower from 280 to 470. Engine options for the Model 367 include the Caterpillar C15 and Cummins ISX, with horsepower from 305 to 600.

Allison automatic transmissions will be available on both the 365 and 367, Marko says. Allison’s 4000 series transmissions come with speeds ranging up to seven on the 4700.

Freightliner’s News
Since January 2006, Freightliner has introduced four configurations of horizontal and vertical after-treatment devices (ATDs) and tailpipes, says Ivan Neblett, manager of product strategy. One installation locates the ATD under the right-side cab entry step. No additional heat is introduced into the cab due to design and insulation technology. Configurations allow for a clear space back-of-cab and for transmission-mounted PTO shafts. The company will continue to offer chromed vertical stacks through the use of high-temperature resistant coating technology inside the stacks.

On Detroit Diesel Series 60 engines, Freightliner offers electronic variable geometry turbochargers, dual solenoid unit fuel injectors for precise fuel rate control, and an optimized EGR system that slashes NOx emissions by more than 50%. Plus, Series 60 engines feature a crankcase centrifuge that removes oil droplets and returns them to a sump. Engine isolators reduce both cab noise and vibration for enhanced driver comfort.

On its MBE4000 engines from Mercedes Benz, Freightliner features its SMART fuel system with dual solenoid unit injectors. The Mercedes Benz engines also have an improved engine brake with a proprietary braking mechanism integrated into the exhaust manifold. An electrostatic crankcase breather ionizes oil droplets and separates them from crankcase vapor through the use of electrical fields. Oil droplets are returned to the sump and clean air is vented to the atmosphere.

What’s more, Freightliner now offers Allison 3000 series automatic transmissions with Shift Energy Management, which allows higher torque engines in a “value engine-transmission package,” says Neblett.

Freightliner mounts its radiators to the engine, which creates less relative movement between the radiator and engine. Plus, there’s less potential for hose and clamp leaks. Maintenance costs are reduced. And there are no cab-mounted radiator struts, which reduces the transfer of engine vibrations into the cab and improves engine access.

Sterling’s L-line
Sterling says the rate of exhaust gas recirculation has increased in 2007 models, which reduces the level of NOx gas emissions. Matt Gervais, Sterling product manager, says the company’s after treatment device has two sections: an oxidation catalyst section and the particulate filter itself. The oxidation catalyst retains heat and drives the collected heat up into the particulate filter, which reduces the soot collected to ash.

“The engine runs a little warmer, so we increase the size of our cooling packages,” says Gervais. That means a larger radiator. For trucks that do not require front frame extensions, the radiator is mounted to the frame rail with drop castings or brackets. For trucks that do require front frame extensions, the frame rails splay outward and forward around the radiator.

Sterling continues to offer its L-line of construction trucks in four bumper-to-back-of-cab dimensions: 101 and 111 inches in set-forward axles; and 113 and 122 inches in set-back axles. “The most popular dump truck is the 113 BBC,” says Gervais, “And the second most popular is the 111.”

In medium-duty L-line trucks, Sterling offers Mercedes Benz and Cummins engines with horsepower ratings up to 330 hp for both engine makes.

Sterling’s other medium-duty truck is the Acterra, in which you can spec a Mercedes Benz engine up to 300 hp, a Cummins ISC engine, or a Cummins ISB up to 300 hp.

On its heavy-duty L-line of trucks, Sterling offers four engines:

• The Mercedes Benz MBE4000, a 12.8-liter engine rated from 350 to 450 hp
• The Detroit Diesel Series 60, a 14-liter engine rated from 425 to 515 hp
• The Caterpillar C13, a 12.5-liter engine rated from 305 to 470 hp
• The Caterpillar C15, a 15.2-liter engine rated from 435 to 550 hp

Kenworth Features Caterpillar and Cummins Power
“Kenworth will offer 2007 Cummins and Caterpillar engines for its Class 8 models,” said Mike Dozier, Kenworth’s chief engineer. Kenworth’s Class 8 engine lineup will include Cummins ISX, ISM, and ISL engines. Caterpillar engines include the C15, the C13, and, new to Kenworth, the C9 for vocational configurations.

Like other manufacturers, Kenworth says it has developed new high-performance cooling systems to enhance reliability, durability, and heat transfer performance. The company has undertaken extensive validation testing of representative vehicle, engine, and emission systems. Dozier says this testing has provided millions of miles of performance data to support the development of system reliability.

At the Mid-America Trucking Show in March 2006, Kenworth introduced a GPS navigation system on its T600, T800, and W900 Class 8 models. The new system is intended to reduce out-of-route miles and is designed to provide the vehicle’s location to an office computer. Functions of the system include routing, turn-by-turn voice commands, waypoint selection, and multiple route selection. Voice commands are played through the radio sound system.

Western Star, a member of the Daimler Chrysler group based in Redford, MI, builds a dependable construction truck as its 4900 Series. Four engines are offered in the series, says T.J. Reed, product manager:

• The Mercedes Benz MBE4000, rated up to 450 hp
• The Detroit Diesel Series 60, rated up to 515 hp
• The Caterpillar C13, rated up to 470 hp
• The Caterpillar C15, rated up to 625 hp

“In 2007 we’re going to a wide-track Meritor MFS front steer axle,” says Reed. “We will add a new 18,000-pound front axle.”

Western Star mounts its after-treatment device under the cab on the passenger side on some models, to allow for clean back-of-cab access. On other models, a vertical ATD permits you to fit auxiliary or automatic transmissions or a power-take-off inside the frame rail.