Heavy Haulers - Silverado And Sierra Get Serious Upgrades

2015 Chevrolet Silverado 3500 HD

Here’s the heavy-duty truck blueprint: Deliver incredible payload and towing capabilities, come in an abundant amount of variations, offer a powerful diesel engine option. All good for the 2015 Chevrolet Silverado HD and GMC Sierra HD.

Both Chevy and GMC borrow from their lighter-duty brethren’s styling cues: The Silverado has a boxy front end, the Sierra a sleeker face and dome hood. Each design improves airflow for better cooling. Cargo beds are stronger and have two-tier loading, integrated tie-downs and available spray-on bed liners. Standard Corner Step bumpers and EZ Lift-and-Lower tailgates are meant for easier loading and unloading.

2015 Chevrolet Silverado 3500 HD Interior

The stronger cabs have high-strength steel structures and come in regular-, double- (front-hinged rear doors) and crew-cab styles. The light-duty interiors migrate over with more space, quality finishes and storage cubbies, as well as USB ports, power outlets and available Intelli Link connectivity - the ideal mobile office. Sierra Denali HD models are the swankiest, with a large configurable digital display on the main gauges, 12-way power-heated and -cooled leather seats, a heated steering wheel and extra chrome outside.

Drivetrains carry over with the 6.0-liter V8 and six-speed automatic standard. An optional bi-fuel version can run regular gas or compressed natural gas. The heavy hitter remains the 6.6-liter Duramax diesel V8, with 397 hp and 765 lb-ft of torque mated to an Allison six-speed.

2015 GMC Sierra Denali HD

GM says roughly two-thirds of heavy-duty customers choose diesels, so it’s fitting we split our day testing a Duramax-equipped Sierra 2500 and a Sierra 3500. Like the light-duty trucks, these 2500s are impressively quiet on the road. There’s little tire/wind noise seeping inside, thanks to inlaid doors, triple door seals and more sound-deadening materials. Steering is sharp for a large truck, and ride quality is smooth. The hulking 3500 drives similar to the 2500: comfortable, quiet, downright relaxing. The 3-ton vehicle’s whole experience is strangely carlike.

With its trucks’ comfort established, GM flexed its muscles, pitting the Silver- ado 2500 HD against the Ford F-250 Super Duty and Ram 2500-all diesels. Towing a 10,000-pound trailer, the Chevy beat the duo drag-racing up a 6-percent grade from a 45-mph roll. A cruise-control test with exhaust brakes going downhill was more interesting. With the three trucks’ cruise set at 55 mph, the Silverado stayed within 5 mph at all times, while the Super Duty and Ram both raced ahead.

2015 GMC Sierra Denali HD Boot / Trunk

So GM’s latest heavy-duty trucks have a 7,374-pound maximum payload, 19,600 pounds conventional max towing, more than 150 model configurations and a Duramax diesel available. The necessary basics are thus satisfied; but a high-refinement level on-road and in the cabin make them better than the competition.