TRUCK TRACKS

By: Ken Kelley

The first new models for the year 2001 have just been unveiled by General Motors’ two truck divisions.

Featuring all-new diesel engines and five-speed automatic transmissions, these 2001s are designed to handle demanding work. The trucks will be Silverado units from Chevrolet and Sierras from GMC, and will be available in the rugged 2500HD (Circle 900), 3500 (Circle 901), 3600 (Circle 902) lineups.

Specialty models to handle demanding work, such as Crew Cab trucks, Big Dooleys with four rear wheels and chassis-cab units for mounting of bodies built for specific jobs abound also will be showcased.

"GM’s all-new, full-sized pickups have set new industry benchmarks," said Gary White, vehicle line executive with the GM Truck Group. "In this case, we have parlayed our relationships with Isuzu, the world’s largest producer of diesel engines, and Allison Transmission, the world’s largest maker of commercial-duty automatic transmissions, to create a powertrain combination that will deliver more of just about everything to truck customers with heavy-duty or commercial requirements."

The new models will be powered by the Duramax Diesel 6600 (Circle 903). The producer said "it is positioned to help GM set new industry standards for diesel power, performance, durability, reliability and quiet operation."

This diesel is the second product of the GM-Isuzu joint venture (DMAX Ltd.) to be unveiled. It was preceeded on the market by a 7.8-liter engine for GM medium-duty trucks for model year 2000, and will be produced in a brand new factory in Moraine, Ohio.

The 6600 is a new 90û, direct-injection overhead valve (four valves per cylinder) turbo-charged V-8 with aluminum high swirl cylinder heads. Other engine features include novel charge air coolers, integral oil coolers, piston spray coolers, transmission oil coolers and 21-in. composite fans. Horsepower and torque ratings will not be published until next fall.

The producers said the 6600 engines will deliver top fuel economy thanks to wide use of aluminum parts and selection of a new Bosch direct-injection, common-rail fuel system. Also noted was careful placement of small components around the basic engine, such as putting the turbocharger in the engine’s V.

GM is counting on Allison Division's 1000 series five-speed automatic transmission (Circle 904) to help deliver the full power and torque of the Duramax 6600. "Superior shift quality and best in class towing capability" were listed among the gear box’s strong points.

The 1000 is set up to operate in one of two modes. The first is for normal operation which delivers top shift quality. In the second tow/haul mode, when the truck is loaded, the transmission is guarded against heat build up.

GM said the 1000 is an electronically controlled transmission that features lockup, overdrive and dual power takeoff drives. The device’s electronic controls "precisely manage shift timing." This capability ensures maximum fuel economy, according to the manufacturer.

Another 1000 strength is a deep first gear that delivers impressive performance in lower gear ranges and superior over-the-road characteristics for smooth and efficient driving and towing.

"The 1000 Series brings Allison Transmission’s proven high standards for durability, reliability and advanced electronic controls to a new truck class," said Dan Hancock, president of Allison Transmission. "With the arrival of the 2001 Silverado/Sierra models, the 1000 Series will deliver Allison Transmission’s solid benefits and bottom-line savings to heavy duty (HD) customers.

"The 1000 series brings toughness and driveability to Silverado/Sierra models —characteristics that are especially beneficial in demanding applications, such as towing and hauling heavy loads. Drivers will appreciate the launch, hill-climbing power and downhill speed control that the 1000 Series delivers," he added.