2004 Chevrolet Avalanche 1500 Z71 Crew Cab Pickup 4-door 5.3l on 2040-cars

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Is the skill of rev matching being lost to computers?

If the ability to drive a vehicle equipped with a manual gearbox is becoming a lost art, then the skill of being able to match revs on downshifts is the stuff they would teach at the automotive equivalent of the Shaolin Temple. The usefulness of rev matching in street driving is limited most of the time – aside from sounding cool and impressing your friends. But out on a race track or the occasional fast, windy road, its benefits are abundantly clear. While in motion, the engine speed and wheel speed of a vehicle with a manual transmission are kept in sync when the clutch is engaged (i.e. when the clutch pedal is not being pressed down). However, when changing gear, that mechanical link is severed briefly, and the synchronization between the motor and wheels is broken. When upshifting during acceleration, this isn't much of an issue, as there's typically not a huge disparity between engine speed and wheel speed as a car accelerates. Rev-matching downshifts is the stuff they would teach at the automotive equivalent of the Shaolin Temple. But when slowing down and downshifting – as you might do when approaching a corner at a high rate of speed – that gap of time caused by the disengagement of the clutch from the engine causes the revs to drop. Without bringing up the revs somehow to help the engine speed match the wheel speed in the gear you're about to use, you'll typically get a sudden jolt when re-engaging the clutch as physics brings everything back into sync. That jolt can be a big problem when you're moving along swiftly, causing instability or even a loss of traction, particularly in rear-wheel-drive cars. So the point of rev matching is to blip the throttle simultaneously as you downshift gears in order to bring the engine speed to a closer match with the wheel speed before you re-engage the clutch in that lower gear, in turn providing a much smoother downshift. When braking is thrown in, you get heel-toe downshifting, which involves some dexterity to use all three pedals at the same time with just two feet – clutch in, slow the car while revving, clutch out. However, even if you're aware of heel-toe technique and the basic elements of how to perform a rev match, perfecting it to the point of making it useful can be difficult.

Next-gen Chevy Silverado and GMC Sierra may use carbon fiber

It's been generally accepted that the next generation of full-size GM trucks will use some sort of strong, lightweight material for the beds while retaining steel for the cab. While aluminum seems like the most obvious choice, according to Automotive News, the Chevy Silverado and GMC Sierra will incorporate both aluminum and carbon fiber in their beds. The publication cites sources from within GM, though it seems the introduction of this comparatively exotic material mix is still a few years off. While carbon fiber is both stronger and lighter than steel and aluminum, it takes significantly more time and money to produce, essentially relegating the material to small-volume cars. The main benefit for trucks is the resulting reduction in weight to improve fuel economy without sacrificing the tough, rugged capabilities truck buyers expect. The Ford F-150 made the switch to aluminum for the 2015 model year and it's proved highly successful. It seemed like it was only a matter of time before the competition followed suit. Automotive News says that the next-gen trucks will launch with aluminum beds and that it will take a couple of years before we'll see any carbon fiber incorporated into the design. Even then, only look for the composite material on higher-trim models, with a trickle down to lower-spec trucks possible further in the future. In 2011, GM announced it was working with Japan-based Teijin Limited on a carbon fiber reinforced thermoplastic. There's a good chance that material's introduction will be on trucks. Related Video: News Source: Automotive News Plants/Manufacturing Rumormill Chevrolet GM GMC Truck

Chevy Express, GMC Savanna reportedly ending production for 2025

The oldest commercial vans on the market may only have a few years left, according to a report from Autoweek. The news outlet cited a "competitive analysis source" in saying that the Chevy Express and GMC Savanna commercial vans would be discontinued after the 2025 model year. They would then be replaced by a new electric van, likely Ultium-platform based, for the 2026 model year. We reached out to GM for comment, and this is the official statement sent to us: "We have said in the past that as part of GM’s larger EV acceleration plans that we will add two new vehicles to our commercial portfolio. The first is a full-sized battery electric cargo van and the second is a medium-duty truck that will put both Ultium and our Hydrotec hydrogen fuel cell technology to work. We have not disclosed timing, names or shared any other details, so any articles reporting more are purely speculative." The GM vans are mighty old, having been introduced for the 1996 model year. They've barely changed since then, having received just some facelifts and updated powertrains over the years. And with GM's electrification plans, we're not surprised that these vans will be on the way out. We do have some disagreement about the reported timeline for replacement, though. We suspect that the upcoming electric vans will overlap with the old vans for at least a year. The reason being that there are a lot of these vans on the road, and there are a lot of pieces of equipment that fit them. Box vans, buses and more have components that have been designed for the Express and Savanna. If you're a fleet that has invested in these components, you might not be ready to shift over to a whole new platform. So GM will probably want to give fleet buyers one last opportunity to replace any old vans before committing entirely to a new electric van platform. It will also be interesting to see what kind of market the GM electric vans enter. Ford already has its electric Transit on the way, and Stellantis will be launching the Ram ProMaster electric van next year. Those are both based on existing gas-powered vans. And GM itself has already delivered the first of its larger BrightDrop EV600 electric vans to FedEx. The coming GM vans will likely be new platforms, which could give them performance and range advantages, though the Ford and Stellantis vans will have the advantage of being compatible with equipment for the gas variants.