Drivetrains: Strictly Business

Anyone still wanting evidence that commercial truck production is a global venture need only pop the hood on that new Freightliner Business Class truck delivering milk at the corner market. The engine could be German, the automatic transmission Japanese, the production strategy “source it where you can find it.”

Freightliner Corp., struggling to keep up with demand for its popular medium-duty line, last month announced plans to buy up to 20,000 Mercedes-Benz MBE900-series electronically controlled diesel engines a year from the powertrain business unit of its corporate parent, DaimlerChrysler, in Stuttgart, Germany. The engine will be standard in all Business Class trucks-FL-50s, FL-60s, and FL-70s-of which Freightliner sold almost 27,000 in 1998.

Freightliner senior vice-president of sales and marketing Mark Lampert calls the deal “the start of a new and comprehensive component-sourcing strategy” between Freightliner and DaimlerChrysler.” The Portland, Ore,-based truck-maker intends to introduce DaimlerChrysler transmissions and front and rear axles in “the next few years,” he says, creating a fully integrated power train. Further details were not forthcoming.

Freightliner is targeting six key vocational sectors for the Mercedes-powered Business Class models: beverage delivery, food services, refuse collection, municipal utilities, towing operators, and emergency services. GVWs could range from 18,000 pounds to more than 33,000 pounds.

Lampert explains that these customers are looking for a high-torque/low-rpm engine that offers a litany of benefits: a high power-to-size ratio and power-to-weight ratio; low life-cycle costs, fuel consumption, emissions, and noise; high engine brake horsepower; heavy-duty durability; wide, flat torque curves; state-of-the-art electronics; optimized maintenance intervals; and an integral engine brake. “The MBE900 family meets or exceeds every one of these criteria,” Lampert says.

Vocational and P&D buyers also want automatic transmissions, which Freightliner complains have been in short supply from Allison Transmission, which dominates that market in North America. So Lampert announced that Freightliner will turn to another offshore source: gearboxes made by Aisin Seiki Co. Ltd. in Japan, a subsidiary of Toyota, and marketed in North America by Aisin World Corp. of America of Downers Grove, Ill. The five-speed Aisin A581 model will be offered as an option on Business Class vehicles beginning this June, with Freightliner planning to buy 60 a month through the end of the year.

“The A581 is engineered to operate with 195- to 230-horsepower ratings of the Cummins ISB engine, but we plan to also offer this transmission with the new MBE900 engine sometime in the near future,” Lampert notes.

Engine Details

Freightliner will offer two displacements and eight power ratings for the MBE900. A 6.4-litre, in-line six-cylinder engine is available immediately, while a 4.3-litre in-line four-cylinder version will be available before the end of the year.

The six-cylinder is rated from 190 to 300 horsepower (peak torque of 860 pound feet @ 1250 rpm), and the four-cylinder model covers ratings from 150 to 190 hp and up to 520 pound feet of torque. Freightliner senior vice-president of engineering and technology Michael von Mayenburg says the MBE900 engines intended for Business Class use are being slightly re-engineered “to provide better ease of service,” he says. For example, the starter and alternator are from Delco Remy.

“We have a fleet of MBE900-equipped test trucks currently in operation to evaluate North American duty cycles, and their activities include extensive operations at both our cold-weather proving grounds in Minnesota and hot-weather tests in Texas. We are also equipping another fleet of trucks for use by our customers to further validate these engines and our modifications before they go into full-scale production.”

Von Mayenburg notes that the Mercedes-Benz engines also will be offered in the specialized vocational products from Freightliner Custom Chassis Corp.

Freightliner’s Lampert says the MBE900 provides superior driveability because it requires less shifting. It also delivers high torque and low rpm: with the 210-hp-rated unit, the torque is nearly 30% higher than a Navistar DT-466, and 35% higher than a T-444E, he says.

“Reduced operating costs can be anticipated thanks to that fact that the recommended oil- and filter-change intervals are 15,000 miles for stop-and-go city driving, and 20,000 miles for mostly highway environments,” Lampert adds. “Also, the engine’s sophisticated electronics will detect any problems before they become critical, and will shut down the engine before serious damage can occur.”

He says the quality of the componentry, including hardened cylinder bores, will add durability. The engine has a chrome-ceramic coating on the first piston ring; a symmetrical piston bowl for even heat dispersion; full-time piston cooling via an oil jet; and seven main bearings for the six-cylinder model and five for the four-cylinder version. Induction-hardened steel is used for the crankshaft and camshaft.

These and other features give the MBE900 an expected life to major overhaul of 500,000 miles. The engine’s environmental rating is also high, since it was designed for the highly demanding emissions and other criteria of Western Europe. All materials used in the unit’s fabrication are either recyclable or burn-disposable.

“These engines are EPA and CARB-certified for 1999 standards, and even crankcase breather fumes are not dumped into the atmosphere, but are burned in the combustion cycle,” Lampert says. “Low emissions are also addressed by increasing fuel-injection pressures to beyond 22,000 psi. The MBE900 produces almost no white smoke at a cold start, and noise levels are just 93 dBa at a one-metre distance at 2300 rpm, thanks in part to a low 600-rpm idle speed.”

The DBE900 family is backed by the full Freightliner warranty system, and once it’s been fully integrated into the product line, more than 600 service outlets across North America will be available to support it.

Lightweight Tranny

Made in Japan, the Aisin A581 five-speed automatic transmission is rated up to 280 hp and 605 pound feet of torque, with maximum engine speed of 3500 rpm. It features full electronic controls for optimal shifting and performance.

The A581 has a single-stage torque converter, and a lock-up in second gear and higher. It can operate in both “power” and “economy” modes: the power mode aids performance on grades, and when the truck is loaded; the economy mode delivers excellent fuel economy for routine operation. “We’ve tested this unit with several fleets and have gotten great reviews, with drivers saying it feels like an automotive transmission,” says Lampert.

Customers will also appreciate the Aisin’s light weight of 360 pounds-about 195 pounds lighter than competitors, Lampert says. “This transmission also offers maintenance advantages,” he adds. “The valve body, fans, and filter do not require adjustment, and the A581 comes with a two-year, unlimited-mileage warranty.”

The A581’s gears ratios are 3.463 in first gear, 2.024 in second; 1.476 in third; 1.000 in fourth; 0.807 in fifth; and 4.179 in reverse. The shift lever is located on the steering column. Lampert says the new pipeline for automatics will help Freightliner boost its 18.7% market share in medium-duty trucks. “We plan to double that market share within the next five years,” he says.

“We’re confident that initiatives such as the MBE900 engine and the Aisin transmission will help us achieve that goal.”