4x4 Duramax Diesel Dually Flatbed on 2040-cars

Auto blog

Redesigned 2021 GMC Yukon gets a diesel, AT4 model, Denali-exclusive interior

GMC's most robust family hauler is getting a complete redesign for the 2021 model year, including a new, off-road centric AT4 model, an upscale interior exclusive to its luxurious Denali model, an available air suspension, and, last but not least, a diesel engine.  With Americans obsessing over trucks, it's no surprise that GMC is going hard with its AT4s-for-everybody strategy; the Yukon is no exception. This will be the first model year for the new trim on GMC's largest SUV. This off-road model gets all the goodies you'll need to veer off the beaten path with confidence, including an extra 2.0 inches of ground clearance with the adaptive suspension option (more below), a two-speed transfer case, standard Goodyear all-terrain tires, an off-road mode for GMC's "Traction Select" drive mode system, hill descent control, and some extra underbody skid plates. Since GMC is a premium brand, even the AT4 gets some luxury appointments, such as a heated steering wheel, heated and ventilated front seats, and heated outboard second-row seats. The interior is also adorned in black leather with tan accents and "AT4" embroidery in the seat backs.  Speaking of premium, GMC will introduce an air-ride adaptive suspension with an off-road ground clearance mode as a late-availability option for several Yukon models, and this feature will be included on the Denali trim.  The Yukon and Yukon XL are GMC's variants of Chevrolet's full-sized SUVs, the Tahoe and Suburban. Their fundamental body-on-frame architecture is also shared with GM's half-ton pickup trucks, and thanks to that common engineering, they can also share powertrains. That's normally just a trivial side note when it comes to a new GM SUV announcement, but this time around, it's a bit more meaningful thanks to the introduction of a new light-duty, inline-six diesel in GM's truck lineup last year.  Yep, that means that for 2021, like the Tahoe and Suburban, the Yukon is getting a diesel option. The 3.0-liter Duramax makes the same 277 horsepower and 460 pound-feet of torque as it does in GM's trucks.  GMC's standard engine is still the 5.3-liter V8 that makes 355 hp and 383 lb-ft of torque. The 6.2-liter V8 is also an option like before, producing 420 hp and 460 lb-ft of torque. All engines come with a 10-speed automatic and a choice of rear- and four-wheel drive.

Trademark application points to evolution of new Hummer EV logo

A trademark application has revealed yet another evolution of the logo expected to adorn GMC's new Hummer EV pickup truck, bringing back the big "H" badge utilized on the H2 and H3 model lines of the expanded SUV lineup's heyday.  The image included with the filing depicts a logo that should be familiar to Hummer fans (or really any American who left their house between 2003 and 2010), with "EV" supplanting the old numerical model indicator. The "Hummer" and "EV" typeface appears to be a direct lift from a filing that surfaced back in April.  This should provide some comfort to folks who are fans of the idea of a future-proofed, all-electric pickup, but want something that embodies the charisma and road presence of the models sold in Hummer's now-deceased, not-so-environmentally-spectacular incarnation. While we don't yet know really any details of the new all-electric SUV, we do know it will be sold via GMC dealers, meaning the revived nameplate will not bring the rest of the Hummer brand along with it.  We haven't really seen much of the new truck, save for teasers and hints here and there. Even the "reveal" back in June only gave us a vague, big-picture look at the truck's silhouette, and various companion images and videos have hinted at features such as a removable roof assembly.  The truck’s general shape is off-road oriented with squared-off, sharp lines tracing the entire silhouette. Its big, knobby tires and blocky wheels are clear indicators of what GM was aiming for with this electric pickup. As for the SUV, comparisons to the Ford Bronco four-door will be inevitable. If our eyes are picking up the scale of this photo correctly, though, the Hummer SUV appears to be a slightly larger vehicle than the four-door Bronco is. Although, the wheelbase for the SUV is shorter than that of the Hummer truck. ThatÂ’ll help it off-road. Those small bumpers and short overhangs along with the bumper cutouts should be hugely beneficial to approach and departure angles, as well. GMCÂ’s shots of the Hummer in the studio are equally as revealing. We can see what looks to be an intense front skid plate and two big tow hooks. In addition to the off-road gear, GMC has allowed a look at the frunk. The front “grille” is one piece with the hood of the truck, so the whole assembly pulls up. That makes for what appears to be a very easy-to-load front trunk compared to other EVs that force you to lift items up and over the front of the car.

'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).