2014 Gmc Yukon Xl Denali on 2040-cars

Auto blog

'Killing a Duramax' Gale Banks YouTube series methodically tunes a diesel to death

Learning or perfecting a skill by watching YouTube videos is known as attending YouTube University. GM Authority picked up on one of the video site's more fascinating courses, hosted by Gale Banks; in a fair world, he should be referred to as Professor Banks when it comes to diesel engines and truck tuning. A few months after GM introduced the updated L5P 6.6-liter Duramax diesel V8 in the 2020 Chevrolet Silverado HD and GMC Sierra HD that ships with 454 horsepower and 910 pound-feet of torque, Banks decided he wanted to methodically tune the engine to death. The purpose of the resulting series, called "Killing a Duramax," is to push more power out of the engine in order to discover which parts break and when — or, as Banks puts it, force-feed the Duramax "until the crank hits the street and the heads hit the hood." With that knowledge, Banks can figure out all the weak points on his way to building what he calls a "Superturbo," that being a supercharged, twin-turbo race engine with more than 1,000 hp. What makes the series fascinating is Banks' knowledge, paired with the company's comprehensive iDash engine monitoring system that keeps tabs on a glut of parameters every step of the way. So for instance, you get Banks explaining the differences between inches of mercury and barometric pressure, how those are different from the water content of the air measured in grains, then showing those readouts on the iDash, then explaining in detail how they affect the air density in the Duramax system. The stock Borg-Warner variable turbo gets a lot of airtime — Banks accuses it of being "out to lunch" because he feels it's the weakest link on the engine. That turns into a turbo teardown and a deep explanation of performance pitfalls, such as when air pressure on the turbine begins to diverge from the boost pressure coming from the compressor. Banks says he can keep close tabs on where power's coming from, because the iDash monitors the horsepower contribution provided by the ambient air, the turbo, and the intercooler separately. The major changes so far are a stouter Precision 7675 turbo and TurboSmart wastegate (episode 5), a twin intake (episode 6), a custom liquid-cooled intercooler from a marine engine, a new GM oil cooler and synthetic oil (episode 10), and new injectors (episode 11).

2022 GMC Hummer Edition 1 weighs 9,063 pounds

From the beginning, the Hummer line of vehicles has been synonymous with the phrase, "absolute unit." The M998 Humvee turned to civilian use as the Hummer H1 came with a curb weight of 7,560 pounds depending on configuration. The much more urbane Hummer H2 didn't sacrifice much of those gains, putting about 6,615 on the scales. Let us not forget that the behemoth gravitational pull and square-jawed mass were what every Hummer buyer wanted. So, starting with the brand values and customer demand, and adding the fact that electric vehicles are substantially heavier than their ICE counterparts, no one should be surprised that the 2022 GMC Hummer Edition 1 weighs 9,063 pounds. That's just one of the substantial figures GMC included in a self-certification filing submitted to the U.S. Environmental Protection Agency, the document rooted out by Car and Driver. Last year GMC told us the Hummer would weigh 9,046 pounds, which proves again the Freshman 15 (or 16) is unavoidable.  Loaded up with humans and their accessories, the truck's gross vehicle weight rating (GVWR) comes in at 10,550 pounds. It takes a few other big numbers to keep that kind of tonnage on the go. The Ultium battery weighs 2,923 pounds. With a 617-amp-hour capacity at 400 volts, total capacity comes in at 246.8 kWh, specific energy at 158 Wh/kg. Usable capacity is about 85% less, at 212.7 kWh. For the time being, these numbers put every other pack in a production vehicle in the shade. That gargantuan chemical plant in the Hummer's floor powers a 329-mile range the same way a giant fuel tanks feed a truck that gets 8 miles to the gallon. The miles per gallon equivalent figures GMC submitted to the EPA are 51 MPGe city, 43 MPGe highway, 47 MPGe combined. Motor Trend questioned whether GM applied the correction factor used for window sticker numbers; if not, the standard 0.7 correction drops the MPGe specs to 36 city, 30 highway, and 33 combined. However, trucks with a GVWR beyond 8,500 pounds don't need to display fuel economy figures on their window stickers, so don't expect to see any such details on dealer lots. For comparison, the Rivian R1T Launch Edition weighs about 7,000 pounds, and fits a 128.9 kWh battery good for an estimated 314 miles estimated at 70 MPGe.

2020 GMC Sierra 2500 HD and 3500 HD spied on public roads

We saw spy shots of the Chevrolet Silverado HD a short time ago, and now it looks like GM has got the 2020 GMC Sierra Heavy Duty trucks running around in public too. The one we're looking at here appears to be a 2500 Denali Crew Cab, distinguished easily by the same Denali grille on the 2019 Sierra 1500. Aesthetic differences between the front fascias on the 1500 and 2500 HD are small, but the 2500 is a bit more muscular in the hood and lower trim treatment. GMC doesn't look like it's hiding a whole lot with this camouflage, since the sheets over the grille and headlights are mostly transparent. The black tarp over what appears to be a hood scoop leads us to believe it will have the same type of hood design as the 2018 HD. Other interesting bits revealed here are around the rear of the pickup. We can see the same interface for the MultiPro six-way tailgate on this truck as the 1500, so at least the Denalis will have the trick tailgate (we'd expect every trim to have it, though). Just like we saw on the Silverado, the Sierra HD gets the stepside feature just ahead of the rear wheels. LED taillights are clearly visible through the thin veiling, and GM's rear steps remain as well. in addition to this 2500 HD, our spy photographers also caught a 3500 HD model. This one isn't a Denali, as the grille shows its hand again. The grille is different than any of GM's designs on the new trucks we've seen thus far, actually. GMC showed us a teaser of what a new Silverado HD grille would look like months ago, but this differs even further than that. It looks rather minimalistic under the sheet for now, with strong horizontal slats. The actual shape and design of the truck is revealed for the most part, since it's just wearing a thin body wrap. Its mirror design appears to be different from last year's, as the arm is completely solid. A sidestep right in front of the rear wheels carries over from the 2500 HD too. We imagine both this truck and the Silverado HD will debut early next year during auto show season. Related video: This content is hosted by a third party. To view it, please update your privacy preferences. Manage Settings.