1976 Gmc Jimmy High Sierra Sport Utility 2-door 6.6l on 2040-cars

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GMC Hummer EV could have had the Chevrolet Avalanche's Midgate

One of the many rumors swirling around the GMC Hummer EV claimed the truck would resurrect the Midgate inaugurated by the original Chevrolet Avalanche. Although we now know there's no way to fully knock down the partition between the cab and the cargo box, the firm revealed the rumor wasn't entirely false. "There was [a Midgate] early on. We opted for the functionality of the drop glass in the back. With the package layout and things like that, it was not advantageous to pursue that one. And, the five-foot bed was kind of the industry standard in regards to price of entry in that segment," explained John Mack, the Hummer's exterior design management, during an interview with Muscle Car & Trucks. The Hummer will go on sale with a five-foot box, and it doesn't sound like a longer bed will be available, so a modern version of the Midgate would have made the model more versatile by giving users the ability to fold down the partition behind the rear seats to carry bulky items, like plywood and ATVs. It's a feature that would have inevitably made the truck more complicated to build, however, because it adds moving parts that need to be sealed. Hinges, seals, and latches in turn add weight, and complexity almost always invites high manufacturing costs. As an electric pickup built with newly-developed components, the Hummer already has enough of each. Motorists who need to carry something that's significantly longer than the cargo box aren't entirely out of luck. As Mack pointed out, the rear window drops into the partition, so owners will have the ability to haul surfboards, lumber, or anything else that's relatively long and reasonably thin by simply pushing a switch. Alternatively, the only thing limiting cargo space when the roof comes off is the sky — or, depending on where you live, bridges. Mack didn't reveal when the Midgate was dropped. GMC launched the Hummer project in April 2019, and it previously released early design sketches that show how the truck transitioned from a sketch to a prototype. As of writing, nothing suggests the Midgate will make a comeback in the near future on any member of the General Motors portfolio. It was introduced in 2001 on the first-generation Chevrolet Avalanche, which went on sale in the United States for the 2002 model year. It later spread to Cadillac's luxed-up variant of the truck, the Escalade EXT, and to the short-lived GMC Envoy XUV.

2022 GMC Sierra Super Cruise First Drive | Now with trailering and automatic lane-changing

Although the updated late-model year 2022 GMC Sierra is still a little ways off (In fact, it hasn't even been revealed), we've had an opportunity to try one of its headlining features: Super Cruise. But it's not quite the Super Cruise you know from the current Cadillac line. The new Sierra will be getting a newer version with two features: the ability to execute lane changes and passes automatically, and the ability to operate with a trailer. We tried the system at GM's proving grounds in Milford, Mich., and our test vehicles were 2022 Sierra prototypes. Though the trucks themselves are early examples with features not finalized, GMC representatives said the Super Cruise system is pretty much finished. The system uses close and long-range radar sensors at the front and a new set of radar sensors at the back, plus the truck's various cameras. It also utilizes the mapping data that GM has accumulated for the system to ensure it operates on approved roads and has detailed information about where the car is. Now, the first new feature enabled by the updated Super Cruise is the automatic lane-change system. The current system can change lanes on its own, but it must be prompted by a press of the turn signal. That feature remains intact, but now, if you approach a slower vehicle on a multi-lane highway, Super Cruise can check the lane next to you to see if it's safe to merge, change lanes, and then return to the original lane once the slow-moving vehicle has been passed. This is where those rear radar sensors come in. We tried it three times on GM's big banked oval course, and it did it impressively smoothly. It was able to make the decision proactively, too, making the decision to change a good distance before we were on top of the slow moving car. Oh, and of course, because this is Super Cruise, it all happened without us having to touch the wheel. Our automatic lane change test was followed by trying Super Cruise with a trailer. Now, it's important to note that the automatic lane-changing functionality won't work with a trailer. This is because that function depends on a set of radar systems at the back of the truck that are blocked by a trailer. Apart from that, the rest of Super Cruise's functions still work just fine. To make this possible (and safe), the system is able to estimate the weight of the trailer and adjust following distance accordingly, allowing it to safely slow down as needed.

'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).