Friday, May 18, 2018

A Short First Drive of the 2019 Chevrolet Silverado

MILFORD, Michigan — Chevrolet’s 2019 Silverado half-ton pickup truck will tackle the base Ford F-150 3.3-liter Ti-VCT and Ram 1500 Pentastar 3.6-liter V-6 engines with an all-new 2.7-liter turbocharged inline four, which it rates 310 horsepower at 5,600 rpm, and 348 pound-feet of torque at 1,500—4,000 rpm. The 2.7 turbo replaces the 4.3-liter V-6 in “High Volume” trim models, though the V-6 remains standard in “High Value” versions.

From a limited, short first drive in a couple of ’19 Chevy Silverados, we’ve got to wonder whether its maker is sandbagging a bit, even though the Ford F-150 2.7-liter EcoBoost V-6 makes 15 horsepower and 52 pound-feet more torque. Our test-driver, an Silverado LT Crew Cab, was quick off the line with virtually no turbo lag, and felt ready to tackle V-8 pickups once in that wide torque band. There was a delay at tip-in from a full stop, but that turned out to be the truck engine’s stop/start system, which unlike Chevy sedans with stop/start, has a defeat button.

The 2.7-liter turbo, which has been designed as a truck engine only, coupled to GM’s 8L90 eight-speed automatic has none of the ponderousness of the 2018 Chevy Silverado LT Crew Cab with the base 4.3-liter V-6 and six-speed auto that General Motors provided for comparison purposes on one of its test roads here. Chevy engineers say the Silverado LT Crew Cab is 380 pounds lighter than the outgoing Silverado LT Crew Cab with that V-6, an engine that carries over only on the “High Value” Work Truck, Custom, and Custom Trailboss trim levels. The 5.3-liter V-8 will be optional on those trucks when they go on sale later this year.

The 2.7-liter turbo four is standard on the “High Volume” LT, RST, and LT Trailboss models (all Trailbosses get a two-inch factory lift kit), and will account for about 10 percent of sales, Chevy says. The 5.3-liter V-8, rated 355 horsepower and 383 pound-feet, also combined with the eight-speed automatic, will be optional. Later in the ’19 model year, the new 3.0-liter Duramax I-6 turbodiesel, coupled to the 10-speed automatic, will be the top option. The “High Feature” LTZ and High Country come with the 5.3 V-8 and eight-speed automatic standard, or the 6.2-liter V-8, rated 420 horsepower and 460 pound-feet, coupled to the 10-speed automatic, and again the 3.0-liter diesel with 10-speed.

We also drove a ’19 Chevy Silverado LT Crew Cab with the 5.3 V-8 and its new, standard Dynamic Fuel Management system back-to-back with an ’18 LT Crew Cab with the 5.3 V-8 and Active Fuel Management. The ’19 Silverado 5.3 V-8 weighs about 450 pounds less than the ’18 Silverado with the 5.3 V-8 and six-speed automatic, in part due to the T1 trucks’ “mixed material” strategy, says fullsize pickup marketing chief Sandor Piszor. The big upgrade in the new model, beyond ride and handling, is that DFM, which GM engineers developed with Thula based on that company’s Skipfire system, deactivates cylinders in any combination from eight down to two, while the outgoing AFM only switches between eight and four.

DFM “makes 80 decisions per second, or one every 12.5 milliseconds,” says Tim Herrick, executive chief engineer for the next-generation full-size trucks. There are 29 available such cylinder modes, but “we’re using 17,” he adds, as the other 12 can cause too much noise and vibration interference. As with AFM in the old V-8-equipped models, DFM will come with both the 5.3-liter and the 6.2-liter engines.

Valves on the DFM V-8 are turned on and off by eight oil control valves, says Joe Folk, assistant chief engineer for the small block truck engines, and DFM operates on average 61 percent of the time with less than eight cylinders, compared with 48 percent for AFM, and it operates with fewer than four cylinders 16 percent of the time.

Unlike AFM, there will be no dashboard display indicating each mode, so Chevy placed a fraction-meter display on the dash of our test truck. The number “1” on the screen indicates running on all eight, with fractions of 1/2 down to 1/4, with other fractions in-between, even 1/3. One-third of eight cylinders?

In this case, DFM is skipping the first and second cylinders, and fires off the third, sixth and back around to the first cylinder, except by now it probably has readjusted to another mode for other torque needs. If we could tell you even a portion of the sequences displayed on the meter, we’d be guilty of distracted driving; it changes that quickly, with no noticeable feel.

The ’19 Silverado is “the best-driving truck we’ve ever built,” Herrick says, and we’d be remiss if we didn’t discuss overall dynamics. The 2019 Chevrolet Silverado is still a full-size truck, which means that unladen, it provides a fairly stiff ride over the Milford Proving Grounds’ real-world test road, though it’s much smoother than the outgoing pickup. As a back-seat passenger on one big bump in particular, the outgoing truck bumped us off the seat surface, while the new one didn’t. It would take back-to-back comparisons to prove, but the Silverado certainly is a contender for best pickup truck ride in the industry. Steering feels light and precise, and a bit quicker than the ’18 model’s.

Chevy says the big new Silverado “drives smaller than it is,” though we’ll wait for a drive in real-world traffic before we can confirm the claim.

We don’t see much future for the High Value 4.3-liter V-6, which gets no substantial upgrades for the ’19 model. The 2.7-liter turbo four and the DFM V-8s, both designed for significant fuel efficiency gains, can squeeze out the V-6 out except on price. The 2.7 is the first of a new four-cylinder engine family, though any other displacement sizes, no doubt smaller in displacement, will be for smaller, lighter cars and SUVs. Engine chief engineer Jordan Lee says it’s designed, contrary to most modern turbocharged fours, to deliver better real-world miles per gallon than the to-be-determined EPA numbers. The turbo four is powerful and torquey enough for GM’s upcoming ’20 model year SUVs, and breathed on heavier than its 22 psi of boost (and 10:1 compression ratio) would make for a dandy Colorado competitor to the inevitable Ford Ranger Raptor.

The 2019 Chevrolet Silverado goes on sale late this summer, but as GM sells down the old model, dealerships aren’t due for significant inventory until the last quarter of this year.

The post A Short First Drive of the 2019 Chevrolet Silverado appeared first on Automobile Magazine.



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