2011 Gmc Sierra 2500hd Denali: Diesel, Nav, Htd/ac Seats, 30k Miles, Like New!!! on 2040-cars

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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.

2013 GMC Acadia Denali

Refreshed, Not Refreshing
I'm probably ill-suited to accurately and fairly take the full measure of a vehicle like the 2013 GMC Acadia Denali. This is a machine conjured around the express notion of corralling and then herding a brood of rafter-swinging hatchlings to and fro in relative comfort, and with no such passel of wee Bowmans to call my own, it's difficult to give this rig a fair shake. While I can certainly weigh cargo capacity, legroom and fuel economy stats with the best of them, I'd be lying to your face if I said the word "crossover" didn't urge some uncontrollable Pavlovian recoil from the murky recesses of my frame. To put it simply, I just can't stand the damn things.
As a rule, the segment is built on a bed of compromise. Manufacturers love nothing more than to spin up a tired yarn about the virtues of this particular neck of the market. We're told the crossbreeds deliver all the ride quality, driving dynamics and fuel economy of a car married with the seating position, capability and interior volume of the SUV set. That all sounds as swell as a sunset, but as the 2013 Acadia Denali so artfully illustrates, the advertising on the box is rarely congruous with the prize inside. Even with an imaginary squad of younglings at my heels, the refreshed luxury crossover doesn't quite manage to scratch the promised itches.

Fullsize GM SUVs have a problem that's making owners sick

Some fullsize SUV owners are getting sick, thanks to a buffeting and vibration problem in 2015 model year examples of the Chevy Tahoe and Suburban, Cadillac Escalade, and GMC Yukon. According to owners' complaints to the National Highway Traffic Safety Administration, the issue can vary from an annoying vibration inside the cabin to an experience so severe that it leads to dizziness and headaches. General Motors is aware of the complaints, but the fix isn't so simple. According to spokesperson Tom Wilkinson to Autoblog, the company "has been tracking this issue for a while." The problem has a fairly low incidence rate, but when it does occur the issue can be "uncomfortable and annoying for owners." There's no precise cause for the issue, Wilkinson claims, and in some cases, simply balancing the tires or changing the door seals can make it go away. However, not all of the fixes are so simple. AutoGuide dug deep into the problem and discovered a GM preliminary information bulletin that advised dealers to remove the headliner and to check the roof's bonds to the bows that go across the vehicle. However, that document included a note that the solution might not entirely eliminate things. According to AutoGuide, adding Dynamat insulation to the roof sometimes helped the problem. A GM spokesperson also told AutoGuide the company fixed the problem at the end of the 2015 model year, and didn't go into any more detail. This roof issue seems linked to some of the worst droning in these SUVs. According to one complaint from a 2015 Suburban owner to NHTSA: "Roof will not remain attached to the roof bows. This causes the buffeting similar to a window being down when all are up. The results span from annoying to painful." A 2015 Yukon owner claims to have another alleged cause for the problem in a NHTSA complaint from February 2015. This person brought their SUV to the dealer seven times over the course of four weeks for vibrations. The dealer replaced the driveshaft, suspension components, and more, but nothing worked. According to an engineer to the service adviser: "In an effort to prevent roll overs, they designed the frame and body mounts too stiff. There are 40 engineers working on issues, they have no solutions that work across the board." Wilkinson told Autoblog that GM is working with customers on an individual basis to rectify things. Since these are newer vehicles, dealers should also fix the problem under warranty.