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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.

2014 Chevy Cruze Diesel arrives with 42 mpg for $25,695*

The last time General Motors had a diesel passenger car in the US, it was the 1.8-liter 1986 Chevette. At the 2013 Chicago Auto Show today, GM is unveiling the much-anticipated 2014 Chevrolet Cruze Diesel. The compact bows with a 2.0-liter turbo-diesel four-cylinder engine that boasts 148 horsepower and 258 pound-feet of torque, with full twist coming on at just 2,000 rpm. What's more, the common-rail, direct-injection diesel features an overboost function that allows the engine to deliver up to 280 lb-ft of torque for 10 seconds at a time. Even with 10 more horsepower and 110 more pound-feet of torque than the available turbocharged 1.4-liter four-cylinder in the Cruze, the 2.0-liter diesel engine can return up to 42 mpg (highway) bolted to its six-speed automatic transmission.
If you're counting, that figure meets the less powerful Cruze Eco with a six-speed manual transmission. More importantly, the auto transmission Cruze Diesel matches its main competition, the Volkswagen Jetta TDI, in highway fuel economy. The Cruze 2.0 TD (as it will be badged) can also handle up to 20 percent biodiesel (B20), whereas the Jetta is rated only for B5. General Motors has not released city fuel economy for its newest diesel, but we do know how much it will cost you to jump behind the driver's seat.
GM will kindly ask for $25,695, plus an $810 destination fee. That marks a $2,115 premium over a loaded Cruze LTZ Auto and $2,640 more than the Jetta TDI, though the MSRP will net you a leather interior, 17-inch alloy wheels and an Aero Performance Package, as well as a two-year maintenance plan and five-year, 100,000-mile powertrain warranty. Compared to the gas-powered Cruze, you also lose a couple cubic feet of rear cargo space thanks to a 17-liter diesel emission fluid tank. That urea fluid, which helps put the clean in clean diesel, will need to be refilled at least every 10,000 miles.

Next-generation GMC Canyon, Chevy Colorado spied together

With the debut of the next-generation GMC Canyon coming in a couple of months (in off-road-ready AT4 guise no less), it's no surprise that both it and the Chevy Colorado are out testing without the heavy coverings of early prototypes. One of our spy photographers caught examples of both trucks with close-fitting vinyl wraps. This gives us a great opportunity to see each pickup more clearly, but also to compare and contrast the designs. From the front, the GMC features a narrower, but seemingly taller grille. At the top are slender lamps. They seem to be daytime running lights, though, and below them are much larger units that will function as the actual headlights. The prototype shown seems to be one of the AT4 variants, based on the lack of a lower air dam and the opened up corners of each bumper. Small fog lights show up in the lower bumper, too. As for the Chevy, its grille is wider, and it blends into the headlights. The lights are at the top of the grille, and they seem to incorporate the actual headlights, not just running lamps. The grille mesh has some interesting detailing, and there are auxiliary lights below the main headlights. This one seems to be a more mainstream Colorado model since it still has a front air dam, possibly a Z71 model, considering the chunky tires. Not surprisingly, the two trucks are very similar from the sides and the rear. They have cabins that look lower, longer and more squared-off than the current models. The fenders look more punched out and aggressive, too. The main differentiator between the Chevy and GMC are the wheel openings. The GMC has sharp corners and the Chevy has more rounded ones, as is the case with the full-size trucks. As previously mentioned, the GMC Canyon AT4 will be revealed this summer, so likely in just a month or two. The Colorado will likely be revealed this summer, too. It's expected that it will use the turbocharged 2.7-liter four-cylinder shared with the Silverado. Naturally, it will be available with two- and four-wheel drive and a variety of trim levels including the AT4 and ZR2 off-road versions. Related video: