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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.

2018 Ford Expedition vs other big SUVs: How it compares on paper

With our Alex Kierstein rightly impressed in his first-drive review of the new 2018 Ford Expedition, we decided to dig a little deeper into the numbers, and we came up with the spreadsheet below to highlight how the new 2018 Expedition compares on paper to its main full-size SUV competitors: the 2018 Chevy Tahoe and Suburban (and therefore the 2018 GMC Yukon), 2018 Toyota Sequoia and 2018 Nissan Armada. We also threw in the new, even bigger 2018 Chevrolet Traverse since, as you'll see, its massive dimensions should put it on the radar for anyone who needs loads of passenger and cargo space but doesn't care as much about towing. A few notes about the chart above. First, the 6.2-liter V8 that's included with the new-for-2018 Tahoe RST trim level is the standard engine on the GMC Yukon Denali. You can apply most of the Tahoe's numbers to the entire Yukon and Yukon XL lineup. Second, though we highlighted categories where the Traverse led, we also highlighted the runner-up full-size SUV, since this was ultimately about that segment. Traverse numbers are broadly applicable to the new Buick Enclave. Related Video: Chevrolet Ford GMC Nissan Toyota SUV Comparison consumer ford expedition gmc yukon chevy traverse toyota sequoia nissan armada chevrolet tahoe ford expedition max