2020 GMC Sierra HD Driven: Refined, Techy, and Big

THAYNE, Wyoming—Back in the 1960s, we saw drawings of the swoopy, voluptuous Car of 2020. So innovative and unlike anything then offered, it would be as self-aware as Maharishi Mahesh Yogi, as powerful as Willie Mays, as fun as a Jimi Hendrix concert. In other words, we knew intuitively there would be eight external cameras, 910 lb-ft of torque, and rear-bumper stereo speakers for raving parties.

It turns out the Car of 2020 is a truck. Neither swoopy nor voluptuous, but certainly crisp and clean, the new GMC Sierra HD advances the pickup art as Andy Warhol advanced pop art nearly 60 years ago. It particularizes a familiar shape, adding a little brawn here and chamfering there, as Warhol particularized the soup can and Jasper Johns did the American flag before him. When everything adds up, the Sierra HD is truly a handsome wonder and capable of dashing from zero to 60 mph in perhaps as quick as 6.5 seconds, yet also pulls a trailer as heavy as 35,500 pounds.

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GMC hosted a preview in northwestern Wyoming, where the all-new Sierra HD stole across the Mormon-steepled towns and whispered through the canyons and valleys, assisting and comforting its driver and passengers in nearly every way possible. Yet the AT4 ground-pounder model, a new addition to the Sierra HD lineup, has enhanced ability to wade, scramble, climb, and descend. It's as if the Sierra wants to prove itself the all-everything vehicle. Besides racetracks, the only thing it does poorly is downtown parking in a fancy city. Depending on your preference in cab and bed configuration, the truck stretches from 19.6 to 22.1 feet in length, so forget parallel parking. And at nearly 6 feet, 8 inches tall, it probably cannot limbo under the crossbar governing admittance to the parking deck.

Big news here is the available 6.6-liter turbodiesel V-8, which produces 445 horsepower and the aforementioned 910 lb-ft of torque as calmly as if it were practicing the Maharishi's meditation technique. From the lack of chugging and rattling, it's easy to mistake this oil-burning V-8 for a gas engine. That is, until we pulled away in the HD Denali 3500 dually with a 40-foot-long, 14,000-pound Keystone Fuzion toy hauler on the fifth-wheel hitch; then a bit of growling and the assertive pull forward revealed the turbodiesel's strength. GMC has found 93 percent of heavy-duty customers will in fact be towing. ("We know the trailer industry at a subatomic level," bragged executive chief engineer Tim Herrick.) It's easy to see why about three-quarters of those buyers will choose the fuss-free turbodiesel Hercules under the hood.

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When Warhol was confounding the world with his silkscreens of Marilyn Monroe, we had three- and four-speed automatic slushboxes in our vehicles and never imagined such a wonder as the Allison 10-speed automatic, a GMC exclusive. More typical of a Class 6 commercial truck, the Allison makes close-ratio shifts the way the Beatles had successive chart-toppers in 1964. This transmission works with the torque-monster engine to ensure authoritative throttle response and no over-revving. Another big-truck feature is the compression brake, activated by a center-console switch, to control downhill speed. GMC claims that with this powertrain, the Sierra can buckle up to an 18,000-pound trailer and still rumble from zero to 60 mph in 19.9 seconds.

For the 20 to 25 percent of buyers who don't want to search for a diesel pump or check the diesel-exhaust fluid's level, a 6.6-liter direct-injection overhead-valve gasoline engine is available; the D.I. is a segment first. This engine makes 401 horsepower and 464 lb-ft of torque. The gas engine is paired with a six-speed automatic, but we can say nothing of its road performance, having driven only the diesel. Because no Sierra HD model weighs less than 6,000 pounds, it's safe to say you shouldn't expect a bullet.

To satisfy every modern-day need, the Sierra HD is available in regular, double, and crew cab in 2500 (three-quarter-ton) or 3500 (one-ton) layouts. Dual rear wheels are available, as are conventional receiver-hitch or fifth-wheel towing arrangements. Trim levels are WT, SLT, SLE, Denali and AT4. The Denali sparkles with chrome and suits the well-heeled customer who likes a feature-laden truck; the Denali sub-brand rings in an average transaction price of $54,000, just below Mercedes-Benz ($57,000) and ahead of Jaguar ($53,000).

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The AT4, introduced last year on the light-duty Sierra 1500, "surprised" GMC with its success, said Phil Brook, vice president of marketing. Rolling on optional 34-inch outside-diameter Goodyear Wrangler Trailrunner tires and wearing signature red tow hooks and a unique grille, the HD AT4 will appeal to the slightly more adventurous set. We spent a morning in an AT4 attached to a box trailer loaded with concrete slabs, and despite the tires' off-pavement tread pattern, it displayed the same civility as the Denali. Of particular delight is the hydraulically assisted steering, which in combination with independent front suspension gives the truck a good turn-in response and requires a satisfyingly firm hand. Yes, the human component is still necessary in 2020.

But a huge amount of onboard computing power is part of the story, too. Even GMC customers who regularly tow trailers reveal anxiety about what they're doing, so the Sierra HD addresses these qualms with eight available cameras and up to 15 "stitched" views. The composite real-time images are accessed through an app on the central display. The full list should begin with Ecclesiastes 3:1: "To everything there is a season, and a time to every purpose under heaven." There is hitch view, useful for attaching to a receiver; bed view for a fifth-wheel trailer; inside trailer view to see your concrete slabs; bowl view for avoiding tall objects when backing up; and the accessory rear trailer view to inform the driver what vehicle is behind. Really, the Byrds could make a record about it. Meantime, front side view and rear side view may be God's way of saying that if you need cameras to find the curb, the truck is too damn big.

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Another cool feature is the side view that appeared onscreen when we signaled a turn. Our bedazzlement quickly ended, though, and we found ourselves looking instead at the big dual side mirrors, which worked fine. Nevertheless, being "woke" in 2020 means we admit the need for help in hitching, backing, and cornering.

While playing to a captive audience in Wyoming, GMC also showed off the Sierra 1500 half-ton with the new 3.0-liter inline turbodiesel six, branded Duramax like the big 6.6-liter turbodiesel V-8. (And which we drove in the Chevrolet Silverado 1500.) It helps expand the lineup in a useful way and offered more evidence of GMC's thoroughness.

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It would be possible to go on listing the amazing features and functionality of the Sierra HD and press our point about it being "The Car of 2020." But we offer this illustrative conclusion instead. While in Wyoming, we sent our neighbor at home two photos, one of the Sierra HD AT4, the other of the spectacular and evocative Grand Teton mountains, so called by lonely French explorers who chose the name in fond tribute to their countrywomen. But our neighbor ignored the mountains. "Nice truck!" he replied.