General Motors adds factory-engineered four- wheel-drive capability to the C4500 and C5500 medium-duty truck models for off-road fleet applications such as those found in utility work, forestry, snow plowing, and landscaping. The 2005-model-year Chevrolet Kodiak and GMC TopKick medium-duty trucks offer off-road capability with factory-engineered four-wheel drive on C4500 and C5500 models. Four-wheel-drive Kodiaks and TopKicks began production in July at the Flint Assembly Plant in Flint, Mich. “The GM-installed four-wheel-drive option is something commercial customers and dealers have been asking for,” said Elliott Benson, product manager for the Kodiak and TopKick C4500 and C5500 models. “This response should exceed customer expectations across a wide range of industries, including forestry, snow plowing, landscaping, agriculture, tree trimming, utility work, and more.” As Benson explained, many of these commercial users operate their vehicles off-road, where traction is critical. Being stuck at a work site - or not being able to reach the site - can carry tremendous costs for owners. “Not only are these 4x4s able to get to the job, they bring with them enhanced agility. These trucks can make surprisingly tight turns in confined areas, providing a tremendous advantage, whether you’re plowing a parking lot or maneuvering in a tight construction site,” Benson said. Four-wheel-drive Kodiak and TopKick models, for example, are available in a variety of wheelbases - ranging from 152 inches (386 cm) to 235 inches (597 cm) - in both Regular Cab and Crew Cab configurations. The standard engine is the Vortec 8100MD V-8 gasoline engine or the available Duramax 6600 V-8 Turbo Diesel. Both powertrains are mated to the Allison 1000 Series five-speed automatic transmission. Enhancing these vehicles’ off-road capability is an electronically controlled New Venture Gear Model NV273 two-speed transfer case, and an instrument panel-mounted rotary selector switch for 4L, 4H, and 2H drive settings. Four-wheel-drive Kodiak and TopKick models also feature manually activated front-locking hubs for additional traction capability and a heavy-duty off-road skid plate to protect the transfer case. To maximize engine power for various operating conditions, all C4500/C5500 Series Kodiak and TopKick models feature electronic throttle control. It permits throttle progression to be optimized, giving the medium-duty 4x4s outstanding throttle control for slow-speed parking lot maneuvers, as well as an immediate response when power is demanded under the most rugged off-road conditions. Warranty Coverage Enhanced for Allison Transmissions
To better meet the needs of vocational applications, many of the Allison transmissions have been recalibrated, and they’re now backed by longer warranties for 2005. For example, the Allison 1000 EVS - used with fire, rescue and ambulance packages on C4500/C5500 models - features a five-year, unlimited mileage, limited warranty. A two-year, 100-percent parts and labor coverage warranty, plus a three-year extended transmission coverage back the Allison 1000 MH and 2200 MH - featured on C4500/C5500 motor home series. Mileage coverage is extended to 200,000 miles. Allison vocational transmissions also are added on the 2005 C6500 and C7500 models. A 2500 HS Allison transmission replaces the 2000 Series transmission in all applications. The 2500 HS allowed a gross vehicle weight rating (GVWR) increase to 33,000 lbs. for 2005 versus 30,000 lbs. for 2004. The Allison 3000 RDS close-ratio six-speed automatic transmission becomes the base transmission on C8500 models and is available on C6500 and C7500 models. A number of other transmission choices are also available. Reliable, Durable, and Efficient The medium-duty trucks include a unique service design, called “Priority Access System,” which integrates components into major modules within the engine compartment. This allows groups of parts to be removed by a technician either independently or in sequence, depending on how much accessibility is required. Other upgrades have been engineered to increase reliability and lower the overall cost of ownership. In 2005, C6500-C8500 models use a 120,000-psi heat-treated frame for an even stronger frame rating. Compared to C4500 and C5500 models, C6500-C8500 feature larger frames and offer a wider selection of wheelbases and single and tandem rear-axle configurations to accommodate larger bodies. Single-axle models can easily accommodate bodies up to 30 feet (9.1 m) without requiring any extra-cost frame extensions. Braking system design improvements include longer design life and a simpler disc-brake-pad removal and replacement process. The electrical system has been redesigned to take advantage of new multiplexing technology, meaning fewer wires and connections doing more work with less complexity. New Braking System
C4500-C7500 models feature new hydraulic four-wheel anti-lock disc brake systems with standard four-channel ABS, electronic brake distribution, and available traction control. The C4500 and C5500 trucks use two systems to optimize performance for particular GVW requirements, with both offering reduced stopping distances, lower pedal effort, and quieter, longer-life operation. C6500-C8500 models, meanwhile, feature low-drag, opposed four-piston, fixed-caliper brake design with diameters sized to particular GVW load requirements. Premium, high-capacity 70-mm, four-piston brake systems are now standard on both the front and rear. All Crew Cab models feature the HydroMax brake booster for brake actuation. Both HydroMax and Hydroboost (used on some conventional cab vehicles) operate on the same principle, with the power steering pump supplying the booster power. A tandem (split) master cylinder provides the independent front and rear circuits for the hydraulic brake system. Sensors warn the driver of “low fluid” or secondary brake failure. Expanded Model Range
The Kodiak and TopKick C4500 and C5500 Series are available in Crew Cab, Regular, and Commercial Cutaway Chassis Cabs, as well as vocational packages to cover fire and rescue, ambulance, shuttle bus, wrecker, and snowplow requirements. For larger tasks, the Kodiak and TopKick C6500, C7500, and C8500 Series (Class 6, 7, 8) trucks feature Regular and Commercial Cutaway Chassis Cab offerings, along with the Crew Cab and T-Series. This model range also includes LoPro (low profile) and Tandem axle variants.