2015 Chevrolet Silverado 2500 Ltz on 2040-cars

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GM execs fired over fraudulent India emissions testing

General Motors hadn't had a recall in India since 1995. That changed when it was discovered that certain employees were playing tricks with local emissions testing in order to ensure passing grades for engines. More than ten GM Powertrain employees in India and the US have been let go over the ensuing emissions flap, including Sam Winegarden, VP of global engine engineering, a man who has been with the company since 1969, leading development of some marquee powerplants.
According to Automotive News, an internal investigation revealed that employees "violated testing procedures," sometimes swapping specially prepared low-emissions engines during testing regimes for the Chevrolet Tavera SUV equipped with the 2.0-liter and 2.5-liter engines. Employees were also manipulating weights in order to get vehicles placed into different emissions categories. The discovery has led to GM recall the 114,000 Taveras produced over an eight-year period and halting their production and sale.
The Economic Times of India reports that the issue is due to "a faulty component." GM has developed a solution to the issue, and once it is validated in testing and approved by the Indian authorities, the recalled vehicles will be fixed at dealers and production will resume.

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.

2020 Chevy Silverado HD vs. 2019 Ram, Ford heavy duty trucks: How they compare on paper

Last year was all about the latest in light-duty full-size pickup trucks, so this year, Ram, Ford and Chevy are launching the heavy-duty variants. The first out of the gate is the redesigned 2019 Ram 2500 and 3500 HD, and Ram dropped all the pertinent specs with the reveal. Chevy followed with the new Silverado HD in Chicago, and Ford revealed updates to the Super Duty at the same show. Ford hasn't released details on output, payload capacity, towing capacity or pricing for the updated Super Duty. As such, we'll be comparing the current Super Duty with the all-new Silverado HD and Ram HD. Both Chevy and Ram have revealed full specs for each of their respective trucks, leaving out only pricing, which we've estimated based on the outgoing models. You can see the raw details in the chart below, followed by extra information and analysis. Some things to keep in mind: These specifications cover all versions of the Ram HD, Silverado HD and Super Duty, such as 2500 and 3500 models, and all the way up to F-450. Specifications can vary widely based on engine, drivetrain, cab and bed configurations, so be sure to take a close look at the specific model you're interested in when you get particularly serious about buying. And of course, be sure to check out our car comparison tool if you'd like to look at other trucks on the market. Engines and drivetrains All three of these trucks offer gasoline and diesel engines, but only the Ram has two versions of the diesel. Starting with gas engines, Ram's 6.4-liter V8 has the power advantage with 25 more horsepower than the next-most-potent Super Duty, but the new Silverado HD's 6.6-liter V8 takes the torque crown at 464 pound-feet, nearly 35 more than the other two gas engines. The Ram is also the only one to pair an eight-speed automatic with the gas engine, whereas the Ford and Chevy make do with a six-speed. With diesel engines, horsepower is a weak point for the Ram. The Ram's entry-level turbo 6.7-liter inline-six is the weakest, as the only one with under 900 pound-feet of torque and under 400 horsepower. Even the high-output version only makes 400 horsepower, while the Chevy makes 445 and the Ford 450. But the tables turn with torque, as the Ram makes a best-in-class 1,000 pound-feet followed by the Ford's 935 and the Chevy's 910. Both the Ram and the current Super Duty diesels each get a six-speed automatic, but the new Silverado HD's diesel gets a 10-speed unit.