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Diesel Power finds the ultimate modified oil-burner

For nine years, Diesel Power magazine has run the Diesel Power Challenge, this year's grindfest being "a week-long torture test that features seven events, nine trucks, 8,000 horsepower, and nearly 15,000 pound-feet of torque." The road to being crowned "the most powerful truck" starts with a dyno run, and then continues through the completion of a CDL-style obstacle course, an eighth-of-a-mile drag race while towing a 10,000-pound trailer, a quarter-mile drag race without a trailer, a fuel economy test in the mountains and finally a sled-pulling test through a 300-foot-long packed-mud pit.
What kind of trucks get into such a fight? Last year's winner, for instance - who upgraded his truck this year to prove he didn't "luck into the win" - drives a 2008 Ford F-250 Super Duty with a 6.4-liter Power Stroke V8 upgraded with a custom intake, Elite Diesel triple turbos and a two-stage nitrous system. Another competitor has a 2005 Dodge Ram 2500 powered by a 5.9-liter Cummins inline-six, upgraded with Garrett turbos, dual-stage nitrous, a seven-inch exhaust stack and twin fans built into the bed to cool the Sun Coast Omega transmission. The numbers on that truck: 1,255 horsepower, and 2,063 pound-feet of torque at the wheels. Naturally, as the image above might suggest, things don't always end well.
You'll find all five videos covering this years challenge below. A scene in the dyno video sums it all up perfectly: a competitor leaves his nitrous on too long and the crew is treated to some ominous poppings, he leans out the window, throws both hands up and shouts, "Amer'ca!"

2015 Chevy Silverado, GMC Sierra heavy duty trucks unveiled

Proving just how important trucks are in the Lone Star State, General Motors has chosen the State Fair of Texas to reveal its new heavy-duty trucks from Chevrolet and GMC. Looking to take some of the wind out of the sails of the 2014 Ram HD and 2015 Ford F-Series Super Duty, the 2015 Chevy Silverado HD and 2015 GMC Sierra HD will have plenty to brag about when they go on sale in the first quarter of next year.
The bragging starts right up front with two available engines. The standard engine is a Vortec 6.0-liter V8 that produces 360 horsepower in the 2500HD and 322 hp in the 3500HD to go along with 380 pound-feet of torque in all applications. The true benefit of this powerplant is that buyers can opt for it to run on straight gasoline, E85 FlexFuel or even compressed natural gas (CNG). For maximum towing and even more flexibility, the 6.6-liter Duramax turbodiesel B20-capable V8 is the way to go, with its carryover 397 hp and 765 lb-ft of torque. Though the max towing abilities of 23,200 pounds (with a fifth-wheel trailer) are less than the 30,000-pound rating of the new Ram, the GM HD trucks offer better conventional trailer towing (19,600 pounds) and payload (7,374 pounds) than rival heavy-duty trucks...for now. The Duramax is paired with a six-speed Allison automatic transmission, while the gas engine gets GM's six-speed Hydra-Matic - no manual transmissions are offered.
Including the engines, GM continues to offer a broad range of configurations (more than 150, to be exact) including three cabs, two cargo bed lengths, numerous trim levels and, of course, the choice of single- or dual-rear wheels on the 3500. The HD trucks have faces that are similar to their half-ton counterparts, with the exception of a larger grille and bigger for improved air flow, and like the current HD offerings, the new Silverado HD and Sierra HD DRW models feature a one-piece bed design incorporating the fender extensions.

GM will no longer remove parts from trucks to calculate curb weights

Following last week's mild uproar after it was discovered that Ford and General Motors were removing some optional parts from their pickups to lower the curb weight and consequently increase the maximum payload, GM has come out and committed to a base curb weight for its upcoming Chevrolet Colorado and GMC Canyon compact trucks (although it has yet to publish them) and its current Silverado and Sierra. The company will do the same for its heavy duty offerings, although those numbers have not been finalized yet.
"This will make our curb weight and payload specs more consistent with those of most other truck makers, making it easier for customers to compare vehicles," GM spokesman Tom Wilkinson told Autoblog in an emailed statement.
As GM notes - and as every manufacturer has noted since this story broke - customers still shouldn't take max payload ratings as gospel. Instead, they should refer to their truck's Tire and Load Label, like the one shown at the inset, which will offer detailed information on max payload, specific to their truck.