2003 Gmc Yukon Xl 1500 Denali Sport Utility 4-door 6.0l on 2040-cars

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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.

GMC unveiling 2021 Yukon, Yukon XL on January 14

UPDATE: We received a reply back from a representative at GMC confirming that the new Yukon will be revealed on January 14. The text has been updated to reflect this. General Motors is renewing its body-on-frame SUVs, and GMC's Yukon is next in line to receive a full makeover. It's scheduled to break cover on January 14 alongside the long-wheelbase Yukon XL. It's reasonable to assume we would have gotten our first glimpse at the next Yukon during the 2020 Detroit Auto Show had the event not moved to June. The new date is too close to the model's on-sale date, so GMC will unveil it during a standalone event held in Vail, Colorado, according to GM Authority. We reached out to GMC, and a representative confirmed that is indeed the reveal date for the full-size SUV. Spy shots suggest stylists took GMC's two biggest SUVs in a sharper, bolder direction. Both models share the same front end, which borrows styling cues like C-shaped headlights from the Sierra pickup. Brand-specific rear lights help the Yukon models stand out from their Chevrolet-badged siblings, the Tahoe and the Suburban, which hasn't always been the case. The standard Yukon and the Yukon XL will each grow in size, though there's no indication GMC's naming structure will change to reflect that; Yukon XXL admittedly doesn't have much of a ring to it. While we haven't seen the interior yet, we expect it's getting a generous serving of technology, including a new, touchscreen-based infotainment system. The larger exterior dimensions will clear up more space for people and gear, so average-sized adults will be able to fit in the third-row seats. The range-topping Denali variants of both models will return to satisfy those who crave sumptuousness. The sheet metal will hide much of the same hardware found under the Tahoe/Suburban duo, including an independent rear suspension added in the name of comfort and handling. Powertrain specifications should carry over, too, meaning the entry-level engine will be a 5.3-liter V8 rated at 355 horsepower and 383 pound-feet of torque. The list of options will include a 6.2-liter V8 with 420 horsepower on tap, and we're betting the straight-six turbodiesel available on the Bowtie-badged SUVs will also be offered at an extra cost. Rear-wheel drive and a 10-speed automatic transmission will come standard, and buyers will be able to pay extra for four-wheel drive. The next GMC Yukon and Yukon XL will go on sale halfway through 2020 as 2021 models.

2014 Chevrolet Silverado and GMC Sierra debut all-new designs, three new engines

General Motors has finally dropped the curtain on the 2014 Chevrolet Silverado and 2014 GMC Sierra. Both trucks have undergone substantial revisions with updated versions of the company's 4.3-liter V6, 5.3-liter V8 and 6.2-liter V8 engines. In a shot across the bows of both Ford and Chrysler, GM says it won't use a V6 engine adapted from passenger car applications. Instead, it developed the 4.3-liter engine based on its proven truck-duty architecture.
All three mills will boast direct injection fuel systems as well as a new cylinder head design. Combined with a revised piston, the new engines feature a smaller combustion chamber with a compression ratio of 11:1 or higher depending on the application. Cylinder deactivation and continuously variable valve timing are all part of the recipe, and each engine is paired with a six-speed automatic transmission with auto grade breaking. So far, no fuel economy or horsepower figures have been released, though GM says the new engines will best their predecessors in both areas.
Outside, the trucks feature a number of enhancements to reduce drag and wind noise, and GM claims both the Silverado and Sierra will offer buyers some of the quietest cabins in the class. Extended cab models now feature front-hinged rear doors to allow easier access to the back passenger area, and Crew Cab buyers can now select between a five-foot, eight-inch bed or a six-foot, six-inch bed. Buyers with a mind toward going off road will also rejoice in the return of the Z71 package, complete with Rancho shocks, front tow hooks and additional under-body protection.