2007 Gmc Sierra 2500hd Pick Up Truck on 2040-cars

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Chevy's 6.6-liter Duramax is pretty much all new

To say there's a heated battle in heavy-duty pickups is an understatement, with Chevrolet, Ford, and Ram constantly trading blows of increased torque, horsepower, and towing capacity. The latest salvo is the revised, more powerful turbo diesel 6.6-liter Duramax V8 in the 2017 Chevy Silverado. It has 910 pound-feet of torque, an increase of 145, putting it nearly level with the Ford Super Duty. Here's a closer look at where those gains come from. How exactly did Chevrolet add all that torque plus 48 horsepower? The automaker essentially took a fine-tooth comb to the entire engine. Chevy says it changed 90 percent of the V8, and the cumulative effect of those small changes adds up to big increases. As you might guess, the turbocharger is updated. The larger unit features electric actuation of the variable nozzle turbine (VNT), and what Chevy calls a double axle cartridge mechanism that separates the VNT moving parts from the housing. That helps with heat performance as well, with a claim that the exhaust side of the turbo can run continuously up to 1,436 degrees Fahrenheit. Helping that cause are six exhaust gaskets made of Inconel - an nickel alloy that contains chromium and iron – and upgraded stainless steel for the exhaust manifold. Despite having the same cast iron cylinder block, albeit with some minor enhancements, the engine has new cylinder heads, pistons, piston pins, connecting rods, and crankshaft, which have all been upgraded to handle 20 percent higher cylinder pressures. Alongside the increase in pressure, Chevrolet also increased the cylinder head's structure with a honeycomb design. The pattern features high-strength aluminum with dual layer water jackets that not only improve strength, but also optimize water flow for better cooling. For 2017, the cylinder head also benefits from integrated plenum that aids the engine in getting more air under heavy loads. The cylinder head isn't the only component to get a minor update, as the pistons have a larger diameter pin for improved oil flow. The same detailed improvements has been bestowed to the humble connecting rods (second in our hearts only to the inanimate carbon rod). The new design has the bolts oriented roughly 45-degrees to the rod instead of parallel. The angle split design, as it's called allows for easier passage through the cylinder.

GM Recalling Another 2.7 Million Vehicles In Five Separate Campaigns

The recalls keep rolling in from General Motors, evidently keen to avoid repeating the mistakes of the ignition-switch debacle and clean house. This time they're all coming at once, with five separate recalls announced together covering approximately 2.7 million vehicles. The largest of the five actions involves over 2.4 million units of the previous-generation Chevrolet Malibu and Malibu Maxx, Pontiac G6 and Saturn Aura in order to fix brake light wiring harness, which have been found to be susceptible to corrosion. The recall is separate from the 56k Aura sedans which GM recently recalled over faulty shift cables, not to mention the previous massive recall of 1.3 million vehicles – some of them the same models – but appears to have resulted from the National Highway Traffic Safety Administration investigation that started with the G6 almost a year ago. The second-largest campaign involves the 2014 Chevy Malibu, specifically those fitted with GM's 2.5-liter engine and stop/start system, approximately 140,000 examples of which has been found to have problematic brakes. The issue does not appear to be connected to the recall of 8k Malibu and Buick LaCrosse sedans (also involving brake woes) which we reported upon last week. Four crashes have been reported in such models, but GM admits it's not yet clear if the problem was a contributing factor in the accidents. A further 112k Corvette models from the 2005-2007 model years are being called in for problems with their low-beam headlamps resulting from a flexing relay control circuit wire that's not meant to bend. GM says it is "aware of several hundred complaints" about this issue, but notes that there have been no reports of related accidents. In addition, over 19k examples of Cadillac CTS from the 2013 and 2014 model years are being recalled over windshield wipers that might not work after a jump start. Finally, GM is also bringing in 477 examples of its 2014 Chevy Silverado, Tahoe and GMC Sierra (though not the Yukon) to fix a problem with a tie rod in its steering rack. As ever, all recall repairs will be performed free of charge, and GM is now estimating that recall-related actions this quarter will result in an estimated $200-million charge against its second-quarter earnings. Read the full announcement from GM below for further details.

IIHS gives good ratings to 4 of 8 midsize pickups in crash test

Versions of the Toyota Tacoma, Chevrolet Colorado and GMC Canyon Crew Cab earned top ratings in a new crash test of midsize pickup trucks from the Insurance Institute for Highway Safety, while two versions of the Nissan Frontier earned marginal ratings. But the organization gave poor marks to all eight pickups tested for their dim headlights. Overall, four of the eight pickups evaluated earned good ratings for protecting occupants in all five crash test categories — the Tacoma double cab along with crew cab versions of the Colorado, Canyon and Tacoma. But the poor headlights and lack of an automatic emergency braking system blocked any of the pickups from qualifying for the IIHS's Top Safety Pick awards. The study looked at two pickup body styles using 2017 models: crew cabs, which have four full doors and two full rows of seating, and extended cabs, which have two full front doors, two smaller rear doors and compact second-row seats. It subjected each to five tests, and it evaluated the performance of front crash prevention systems and headlights. The Toyota Tacoma crew cab was the only pickup in that class that earned a good rating for structure in the small overlap test, which replicates what happens when a vehicle clips a tree, pole or another vehicle that has crossed the center line. The model's Access Cab extended-cab version was rated similarly, though its structure was rated acceptable. "This group of small pickups performed better in the small overlap front test than many of their larger pickup cousins," says David Zuby, the Institute's executive vice president and chief research officer. "The exception was the Nissan Frontier, which hasn't had a structural redesign since the 2005 model year." The extended-cab versions of the Chevy Colorado and GMC Canyon earned acceptable ratings, while both the Nissan Frontier king-cab and crew-cab models were rated marginal. Toyota says its 2018 Tacoma will feature upgraded headlights and a standard autobraking system that can detect pedestrians. "Headlights are basic but vital safety equipment. Drivers shouldn't have to give up the ability to see the road at night when they choose a small pickup," Zuby said. Related Video: Auto News Chevrolet GMC Nissan Toyota Safety Truck Videos gmc canyon nissan frontier chevrolet colorado