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GM exploring ways to raise half-ton Duramax diesel tow rating

Lots of truck owners cheered when GM announced fuel economy numbers for the 2020 Chevrolet Silverado with the 3.0-liter Duramax diesel inline-six. Even after Ram let loose its EPA mileage ratings for the 2020 Ram 1500 EcoDiesel, the Chevy oil-burner still took the trophy. The victory was years in the making, GM engineers spending an entire four-year development cycle refining the LM2 Duramax to increase mileage. The tradeoff, as well all know by now, is towing; the Duramax in half-ton duty pulls a maximum 9,300 pounds in the Silverado. Rivals across town can do more, the Ford F-150 PowerStroke rated at 11,500, the Ram 1500 EcoDiesel game to pull 12,560. GM engineer John Barta told Muscle Cars & Trucks that more hauling chops could be on the way, explaining, "We’re actually looking at upgrading some of the materials around (the engine bay) to see if we can maybe raise our tow rating." Engine bay materials are at issue due to thermal complexities underhood. John Barta, GM's assistant chief engineer of diesel engine controls, said the Duramax's inline-six configuration allowed engineers to get emissions hardware like the combined selective catalytic reduction, diesel oxidation catalysts, and diesel particulate filter unit closer to the engine, where it heats up quicker, getting emissions down quicker. But that filter puts another heat source in those confines, enforcing a cap on the tow rating to keep the engine and other systems from overheating. "If you look under the hood," he said, "youÂ’ll see a significant amount of silver ‘moon tapeÂ’ around to make sure things arenÂ’t getting overheatedÂ… if we were to go up in higher towing, which we can, we start impacting the possibility of deteriorating some of the components.” There isn't much space for more grille, so swapping for a better grade of "moon tape" or a different kind of material could reduce engine bay heat, extracting a higher tow rating in the process.  It's important to note a point Barta's been making for months about the Duramax figures, though. "Even though itÂ’s nice to brag about big numbers, in reality, light duty customers are not towing that large with their trucks," and, "We do know that (95 percent) of our light duty customers donÂ’t tow over 9,000 pounds." On our First Drive of the 2020 Silverado diesel we called out the tow rating, but emphasized that the Chevy and GMC have more important challenges to overcome.

Specialty Vehicle Engineering's 750-horsepower GMC Canyon fully revealed

GMC's celebrated Syclone will turn 30 in early 2021, but nothing suggests the company will mark the occasion by releasing a modern interpretation of the pickup. New Jersey-based tuner Specialty Vehicle Engineering (SVE) is taking the matter into its own hands by building a limited number of GMC Canyon trucks with Hellcat-like power. Although the original Syclone received a turbocharged V6, the 2021 model gains a 5.3-liter V8 normally found in bigger vehicles, including the Sierra and Yukon. SVE rebuilt it with forged aluminum pistons, forged steel connecting rods, high-lift valve springs, a custom crankshaft and upgraded fuel injectors among other aftermarket parts. It also added a supercharger to raise the eight's output to 750 horsepower and 600 pound-feet of torque. Power flows to the four wheels via a strengthened 8-speed automatic transmission and a permanent all-wheel-drive system. For context, the first Syclone gave the Chevrolet Corvette a run for its money with a fuel-injected, 4.3-liter V6 turbocharged to 280 horsepower and 360 pound-feet of torque. These numbers were spectacular in the early 1990s since the Sonoma that Syclone was based on shipped with the 105-horse Iron Duke four-cylinder as standard. Even compared with the Sonoma GT that got a naturally aspirated 4.3-liter V6 with 195 horsepower and 260 pound-feet of torque, the Syclone was impressive. SVE installed six-pistons front calipers that clamp 13.6-inch slotted rotors, and it kept the factory brakes out back. It also lowered the suspension by two inches in the front and five inches in the back, upgraded the shocks, and added a heavy-duty rear sway bar. These modifications help drivers make the most of the extra power, but SVE hasn't published performance specifications (like the truck's zero-to-60-mph time) yet. Surprisingly, the eight-cylinder weighs almost the same as the V6 it replaces so the engine swap doesn't affect weight distribution. Visually, the Syclone can't be mistaken for a run-of-the-mill Canyon. It wears a deep front bumper, has cladding over the rocker panels and rides on 20-inch alloys. Edition-specific emblems round out the look, and the list of options includes a body-colored grille as well as a folding tonneau cover. SVE's images show a truck painted black, which was the only color offered on the 1991 model, but it's available in any factory hue. Inside, the modern-day Syclone gains special floor mats and a numbered plaque on the dashboard. Leather is optional.

Chevy Silverado, GMC Sierra 4.3-liter EcoTec3 V6 nets 18 mpg city, 24 highway

There is no doubting that fuel economy has become an important factor in the highly competitive fullsize truck market, with the Ford F-150 EcoBoost V6 and Pentastar V6-powered Ram 1500 setting quite a precedent in recent years. Now it's General Motors' turn. The General has just announced that the new base V6 used in the 2014 Chevrolet Silverado and GMC Sierra 1500 models will return an EPA-estimated 18 mpg city and 24 mpg highway in two-wheel drive trim, regardless of cab configuration.
While these figures don't go so far as to earn GM any "best-in-class" fuel economy claims (thanks to the 25-mpg Ram 1500 HFE), this new 4.3L EcoTec3 V6 does edge the F-150 and Toyota Tundra while boasting best-in-class numbers for torque, payload and towing capacity among six-cylinder rivals. This all-new engine produces 285 horsepower and 305 pound-feet of torque, and it gives the 2014 Silverado and Sierra the highest towing rating among standard V6 models with a 7,200-pound towing capacity - besting the Ram by 700 pounds, the base F-150 by 1,100 pounds and coming within 200 pounds of the V8-powered Nissan Titan. Scroll down for the official press releases from Chevrolet and GMC.