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Chevy says not to look at the 2019 Silverado's fuel economy rating

The 2019 Chevy Silverado is hitting dealerships soon, and one of the most notable changes for the new full-size pickup is the addition of a 2.7-liter turbocharged inline-four. The engine replaces the naturally-aspirated 4.3-liter V6 in volume consumer models like the Silverado LT and promises more power, less weight and — most importantly — better fuel economy. The thing is, the gains in efficiency haven't been as dramatic as some might have hoped, especially when stacked up against competitors from Ford and Ram. As Automotive News reports, GM's response is a little murky. First, let's talk numbers. We're pulling all figures from FuelEconomy.gov, the official U.S. government source for fuel ratings. Fuel economy numbers on trucks vary greatly based on a number of factors. Bed and cab configuration play a part, but so does a four-wheel-drive system. You also have to factor in tires, transmissions, rear-axle gearing, hybrid systems and cylinder deactivation. Things like that can make the difference between best- and worst-in-class. The EPA's website doesn't give enough information a lot of the time, so there's really no easy way to compare apples-to-apples. First, take a look at the ratings for the 2019 Silverado. A 2.7-liter model with two-wheel drive is rated 20 city, 23 highway and 21 combined. That's both better and worse than a two-wheel drive 2018 Silverado with the 4.3-liter V6 (18 city, 24 highway and 20 combined). The updated 2019 Silverado with a 4.3-liter V6 has yet to be rated. With less weight and a smaller engine, many hoped Chevy would make bigger gains. It's unusual to see any decrease in a fuel economy metric these days. GM says that it's not done tuning the new 2.7-liter engine, so fuel economy could theoretically increase. Expanding further, a V8-powered 2019 Silverado (17 city, 24 highway and 19 combined) actually gets better highway fuel economy than a turbocharged four-cylinder powered truck in certain configurations, even if the latter has a better overall average. But that's only with two-wheel drive, the 8-speed transmission and cylinder deactivation. A Silverado with the 5.3-liter V8 and a 6-speed automatic is rated at 15 city, 22 highway and 17 combined. The biggest issue with the Silverado 2.7-liter doesn't come from within GM itself but from Ford and Ram. GM cites the Ford F-150 with the 3.3-liter V6 and the Ram 1500 with the 3.6-liter V6 as the closest competitors to its new 2.7-liter inline-four.

UAW rejects GM contract proposal but makes a counter offer

The United Auto Workers union said a new comprehensive offer made by General Motors Co late Monday to end a two-week-old strike was not acceptable and said it had made a new counterproposal. UAW vice president Terry Dittes said in a letter to members "there are many important issues that remain unresolved." The union is awaiting GM's next proposal. He said GM's offer came up short on many issues.  Dittes said GM made a "comprehensive proposal" at 9:40 p.m. Monday. "This proposal that the company provided to us on day 15 of the strike did not satisfy your contract demands or needs. There were many areas that came up short like health care, wages, temporary employees, skilled trades and job security to name a few." Dittes is the union's vice president for GM relations and the UAW's lead negotiator in these contract talks. "We have responded today with a counterproposal and are awaiting GM's next proposal to the union," he wrote. "Regardless of what is publicized in print or social media, etc., there are still many important issues that remain unresolved." The strike, in its third week, has cost GM more than $1 billion, according to J.P. Morgan analyst Ryan Brickman. He said the cost per day in potential profit is $82 million. However, another analysis, by East Lansing-based consultant Anderson Economic Group, put the losses at $25 million a day. And the effects of the strike are expanding. GM said Tuesday the strike has created a parts shortage that forced the automaker to halt production at its pickup and transmission plants in Silao, Mexico, temporarily laying off 6,000 workers. Silao is where GM builds its highly profitable four-door crew cab Chevy Silverado and GMC Sierra pickups. The strike has also forced GM to idle some Canadian workers, and many suppliers have been forced to halt operations. About 48,000 UAW members went on strike on Sept. 16 seeking higher pay, greater job security, a bigger share of the leading U.S. automaker’s profit and protection of their healthcare. 

'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).