|Dealers size up variable geometry turbocharger, new for Mack's MP series engines. (Photo by Tudor Hampton for ENR.)|
Clean diesel engines that power construction trucks are making considerable gains in fuel economy, but maintenance issues are still up in the air.
Mack Trucks� latest round of low-emission engines, available starting next year, are at least 2% to 3% more fuel-efficient than previous powertrains.
For some construction work, where older, heavy-duty engines have a thirst for fuel, users may even see double-digit percent gains, the manufacturer claims.
The new "MackPower" series represents the Allentown, Pa.-based supplier's most-extensive engine rollout in 40 years, and it is designed to help Mack meet U.S. emission cuts required in January 2007.
Six new engines will lead the charge, with 11-liter displacement, output of 325 to 405 hp and torque between 1,260 and 1,560 lb-ft.
Initially, the MP7 will power the company's updated Granite construction series of trucks and a new, sleek-looking highway truck, called the Pinnacle.
Later, Mack plans to launch another five, 13-liter MP8 engines in 2007, with a class of 16-liter MP10 units to follow. All will use cooled-exhaust-gas recirculation, variable-geometry turbocharging and electronically-controlled injectors, all key methods for reducing diesel smog and soot.
The introduction marks a significant change in Mack�s power-train strategy, using engineering from its Gothenburg, Sweden-based parent company, Volvo Group, while adding its own traditional robustness.
|Vikner. (Photo by Tudor Hampton for ENR.)|
Volvo introduced its own line of 2007-compliant engines on Oct. 17, noting that it has spent $150 million to upgrade its North American engine plant in Hagerstown, Md.
Both firms have dumped loads of cash into research and development for ongoing regulations in the U.S., Europe and Japan. "A lot of R&D must be done to stay competitive," says Jorma Halonen, deputy CEO of Volvo and chairman of Mack.
Starting in January 2007, the engines will change yet again, with the addition of diesel particulate filters, which trap soot in the tailpipe.
By 2010, when another U.S. emission cut takes effect, manufacturers plan to use more aftertreatment components to reduce nitrogen oxides, but they are not ready to discuss specifics.
Made by Cummins� Fleetguard unit, the soon-to-come particulate filters will completely eliminate mufflers on Mack�s construction trucks. They are up to three times as heavy as traditional mufflers. The MP7 is 27 lb lighter than previous engines on construction trucks and 143 lb lighter on highway trucks, which helps counterbalance the extra weight.
Particulate filters require periodic cleaning with expensive soot-disposal equipment in the shop. Dealers say they may opt to send dirty particulate canisters to a remanufacturer, rather than investing in the equipment themselves.
Truck dealers, who are on the front lines of selling clean-diesel technology to contractors, voiced their concerns over the maintenance issues and added costs during an internal sales meeting held Oct. 23 in Las Vegas.
It takes years to help the industry get up to speed with emission changes, they said. Field testing helps speed up the process, but manufacturers "need to get better at building a track record before [the engines] go into normal production," said Pete Witt, sales manager for Virginia Truck Center Inc., Roanoke, Va.
Mack is trying to give extra time for truck owners to test the engines by allowing its customers to choose between the new MP series and older engines until the 2007 regulation goes into effect.
It also gives Mack time to retool. "We feel more comfortable with phase-ins and phase-outs, than Friday-to-Monday," said Mack President and CEO Paul Vikner.
Gains in fuel economy in next-year�s MP engines may encourage truck owners to pick up the new engines early, he added. That may soften the blow of an industry phenomenon known as a "pre-buy," when construction fleet owners stock up on older-style engines in the months leading up to an emission mandate.
Dealers expressed their belief that a pre-buy is likely to happen. "I think it is going on, to some degree, right now," Witt said. Overall, dealers are expecting steady sales through late 2006, with a major slowdown in 2007.