2008 Gmc Sierra 2500 Hd Slt Crew Cab Duramax Diesel 4x4 on 2040-cars

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NHTSA opens safety investigations into Toyota, GM and Honda crossovers

The National Highway Traffic Safety Administration is evidently keeping itself very busy these days, as the federal agency has just announced it is launching or renewing investigations into Toyota, Honda and General Motors crossovers.
2006-2008 model year Toyota RAV4 crossovers are under review for allegations of rear tie-rod rust which can result in failure. NHTSA also said it is probing some 35 complaints about 2005 Honda Pilot models with inappropriate activation of the vehicles' stability control system. The alleged malfunction can cause the vehicles to slow down or stop in bad unsafe situations. At the moment, NHTSA is reviewing a petition regarding the Pilot issue, a move that will determine whether it needs to open a full-blown investigation.
In addition, Saturn Outlook and GMC Acadia three-row crossovers built in 2007-2009 are getting looked at for "loss of low beam headlamp" function. One complainant said the wiring in his Outlook overheated and melted. NHTSA says it has received 415 complaints about the problem and a GM spokesman confirmed that the automaker already started a "Customer Satisfaction Program" in December to address the issue.

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.

2021 Chevy Silverado, GMC Sierra fuel economy to go down due to global chip shortage

Production of the 2021 Chevy Silverado and 2021 GMC Sierra is continuing, but the global semiconductor chip shortage is resulting in a mid-year change. Or rather, an omission.  Basically, the availability of cylinder deactivation for the 5.3-liter V8 will be significantly reduced, resulting in a reduction of 1 mpg combined for affected models. This applies whether that engine has the six- or eight-speed automatic, as well as to both the regular Active Fuel Management and the more advanced Dynamic Fuel Management cylinder deactivation systems. DFM does remain with the pairing of 5.3-liter V8 and 10-speed automatic that comes standard on the LT Trail Boss and High Country. "Due to the micro controller shortage, the components that control AFM/DFM in the engine control module (ECM) have been removed," GM spokesperson Michelle Malcho told Autoblog. She also indicated that the engines will still have the AFM/DFM hardware in place, but that GM will not allow activation of the systems in the future with an ECM change.  Malcho also confirmed to Autoblog that the Silverado and Sierra's other engines will continue to have AFM and DFM, including the 2.7-liter turbo inline-four, 4.3-liter V6 and 6.2-liter V8. In an earlier statement to Reuters, she declined to say the volume of vehicles affected. "By taking this measure, we are better able to meet the strong customer and dealer demand for our full-size trucks as the industry continues to rebound and strengthen," Malcho wrote Reuters in an email. The change runs through the 2021 model year, she said. Malcho told Reuters it would not have a major impact on the Detroit automaker's U.S. corporate average fuel economy (CAFE) numbers. "We routinely monitor our fleet for compliance in the U.S. and Canada, and we balance our portfolio in a way that enables us to manage unforeseeable circumstances like this without compromising our overall (greenhouse gas) and fuel economy compliance," she said. GM's fleetwide fuel economy in the 2018 model year was 22.5 miles per gallon and was projected to rise to 22.8 mpg for 2019, according to a report by the Environmental Protection Agency. To meet federal CAFE requirements, automakers like GM often use credits from either earlier years where they faced less stringent rules and performed better than the requirements or buy credits from other automakers. GM said last month the chip shortage could shave up to $2 billion from this year's earnings.