Restyled, Refined GM Heavy Duty Pickups Close To Production
General Motors Corp. has extended the new styling, powertrain and chassis advancements of its GMT900 light-duty 1500 pickups to the Heavy Duty 2500HD and 3500HD models, with production to begin in the first quarter of the new year. Chevrolet Silverado and GMC Sierra versions feature more distinct exterior styling, and all models will get upgraded powertrains and refined interiors.
The 3/4-ton 2500HD and 1-ton 3500HD pickups come with two-door Regular or four-door Extended or Crew cabs with 6.5- or 8-foot beds and single- or dual-wheel rear axles.
Buyers will choose a Vortec 6-liter gasoline engine or Duramax 6.6-liter diesel, both V-8s. The 8.1-liter gasoline V-8 has been dropped from Class 2 and Class 3 pickups, but is still available in GM's medium- and heavy-duty trucks.
The styling follows the chunkiness of the new 1500s, but has bolder outlines to suggest the 2500/3500HDs' greater payload and towing capacities. Chevies and GMCs get unique hoods, front fenders, grilles, headlights and tail lamps and pickup-box designs. Tolerances between sheet metal panels are tighter, and the gap between the pickup box and cab is said to be half as long as before.
The windshield has a 57-degree rake for low wind resistance and smooth appearance. The Extended cab's rear-hung back doors swing on dual-action hinges to open 170 degrees, folding almost flat against the pickup body for easy loading and unloading on parking lots.
Interior packages are Pure Pickup with a straight-across dashboard, and Luxury Inspired with a center audio and HVAC stack and fancier materials and appointments. There are numerous storage spaces in both trim levels. Special sound-deadening sprays and foams keep the cab interiors insulated from road noise.
The ladder-section frame includes hydroformed box sections in front that contribute to greater stiffness. This, along with rack-and-pinion steering and suspension refinements, make for a smooth and highly controlled ride, according to GM executives. Four-wheel-drive trucks can be had with a Z71 Off Road package, which was formerly limited to 1/2-ton pickups.
The standard Generation IV Vortec 6-liter gasoline V-8 has variable valve timing and is rated at 353 horsepower and 373 pounds-feet. The optional Duramax diesel V-8 has been enlarged from 6 to 6.6 liters and has advanced combustion, air management and exhaust aftertreatment equipment to meet EPA '07 emissions limits. The Duramax's rating of 365 horsepower and 660 pounds-feet is the strongest announced for this segment.
Both engines come standard with six-speed automatic transmissions, a new Hydra-Matic 6L90 for the Vortec and Allison 1000 for the Duramax. No manual transmissions are offered, marketers explain, because few customers bought them in the GMT800 pickups. An integrated trailer-brake controller is now available.
Safety was given considerable attention in the GMT900 pickups, say GM executives. A tire pressure monitoring system is standard, along with large four-wheel disc brakes. Rear-impact sensors work with those in the front air bags to deploy the bags and tighten seat-belt tensioners in front or rear crashes. Cab structures use high-strength steel and special adhesives to resist crushing.
GM's On-Star call-in system is standard, and a radio/navigation system with touch screen and turn-by-turn prompting is optional. Also available are ultrasonic rear parking assist, and power sliding window on Extended and Crew cabs. Stadium-type fold-up rear seats are standard. A variety of tool boxes and cargo securement devices are available, and an EZ Lift tailgate assist using torque rods is standard.
