Comparison Tests
Heavy-duty diesel pickups are the true workhorses of America, with engines making as much as 800 pound-feet of torque and the might to tow an entire fleet of B-Spec racers to the track at once.
Until recently, the towing capabilities that manufacturers claimed for each model were largely conjured up independently in a very public game of chest-pounding one-upmanship. But the Society of Automotive Engineers has lent newfound conformity to towing numbers with the creation of its J2807 recommended practice, already adopted by the players here. SAE J2807 adds credibility to tow ratings by clearly defining the procedures used to determine them.
The key element of J2807’s various tow-vehicle acceleration and climbing requirements, which the SAE modeled on real-world roads, is the so-called Davis Dam test, an 11.4-mile ascent near the dam on the Arizona-Nevada border. Here, a truck has to climb 3000 feet without dropping below 40 mph. Averaging a five-percent grade on Arizona’s Highway 68, the desolate mountain route combines challenging inclines with scenic vistas of the Colorado River, the Davis Dam itself, and the snowbird gambling retreat of Laughlin, Nevada. Along with the surrounding desert roads, it’s the perfect setting for evaluating the latest crop of modern-day draft horses.
The top-spec rigs on these pages start at about $50,000 in four-door, four-wheel-drive luxury trim and, with diesel engines and all the extras, surpass the base price of an Audi A7 luxohatch. More than just work trucks, these overachieving cowboy Cadillacs embody the bigger-is-better ethos, heaping on extra helpings of attitude for their devoted followers. The stakes here are high, the bragging rights incalculable.
Last year saw a wholesale update of the segment, with General Motors reinventing the dirty bits of the Chevrolet Silverado (and GMC Sierra), including a stronger, boxed frame and fortified underpinnings, as well as revisions to the Allison six-speed automatic ($1200) and the 6.6-liter Duramax V-8 turbo-diesel ($7195), now good for 397 horsepower and 765 pound-feet of torque.
Not by coincidence, Ford gave its nearly four-ton F-series Super Duty a new 6.7-liter Power Stroke diesel V-8. That engine—a $7835 option (along with its six-speed automatic)—features a lighter, compacted-graphite-iron block, outboard intake ports, and a novel twin-compressor-wheel turbocharger in the cylinder valley. An even 400 horsepower and 800 pound-feet are the results. Ford also modified the frame, suspension, and steering, and fitted a new chrome face bearing a blue oval that may or may not have started life as a serving platter.
Chrysler, to keep up, also boosted the torque of the venerable 350-hp, 6.7-liter Cummins diesel inline-six ($7195) in its big Ram trucks to 800 pound-feet in late 2011. Featuring an upgraded six-speed automatic ($1100), it is the only powertrain here to use an NOx adsorber rather than urea injection in its exhaust to meet current federal emissions regulations.
To make the trucks actually break a sweat, we enlisted the help of Titan Trailers of Waterville, Kansas, which graciously
supplied us with three tandem-axle, hydraulic dump trailers. We then loaded them with crushed rock for a gross trailer weight of 12,000 pounds each.
Hitching up was easy with the trucks’ integrated trailer-brake controllers and rearview cameras, so we hit the Davis Dam, the open desert, and Las Vegas Motor Speedway to see which pulled best.
