Mountain Wheels: AT4 off-road models of GMC’s truck family boost versatility |

Mountain Wheels: AT4 off-road models of GMC’s truck family boost versatility

GMC’s 2021 Canyon AT4 imbues the company’s midsize pickup with solid off-road credentials but still manageable on-road character.
Photo from GMC


Should you feel the need (or the necessity) to physically flee the country next week, perhaps the litany of hyper-macho, off-road trickery available to truck and SUV purchasers will make your departure all the easier.

GMC has, like other truck makers, figured out that people like big, blocky, off-road ready looks, even if they never get off pavement. And to that end, the 2021 model year AT4 versions of their midsize (ie. smaller) Canyon pickup and the full-sized Sierra 1500 pickup certainly deliver on boisterous, battle-hardened performance and punchier looks. Plus, the Sierra was magically equipped with a light-duty Duramax 3.0-liter diesel engine, just to make it even more bug-out friendly.

My notes remind me that, despite its smaller size and slightly old-school vibe, the $42,585 Canyon was indeed one of my favorites of my whole year of driving. I concluded that this buffed-out Canyon’s simple “get there, take care of business, do not take up an entire parking garage” demeanor was pretty awesome — reminiscent of the early 2000s-era Ford Rangers I used to have (and not particularly like the new Ranger, which we will readdress in a few weeks).

Yeah, it doesn’t have 710 horsepower, and its micro-sized rear cab and short box necessitated me stashing a ski bag over a reclined passenger seat. But it’s not a land yacht like most modern trucks, and with its oversized tires, beefy but highway-friendly performance suspension and attractively simple interior, it was kind of a pleasant throwback to the days of non-$80,000 pickups.

Canyon AT4, which was debuted in Vail last year (guess I wasn’t invited), adds 31-inch Goodyear Wrangler DuraTrac tires on 17-inch aluminum wheels, a locking rear differential and skid plates under the differential, with a 22 mpg, 308-horsepower, 3.6-liter V-6 engine, which I think is more power than the archaic, twice-as-large Lexus GX 460 I drove more recently.

That produces a comfortably capable but still comfortable road-cruising machine, which I again used to get through a foot of snow, resulting in about 200 gallons of mag chloride and traction sand all over its Summit White exterior. I plowed along like I was in a SnowCat — no fuss, no drama, just easy-going road security. I imagine its size also would make summertime trail work a lot easier than a full-sized truck. A larger grille and red recover hooks up front made it stylish, too.

Yes, Canyon’s 4WD control is entirely hidden behind the steering wheel — the dash is too small and the vents too large to get the far superior General Motors 4WD control panel featured on full-sized trucks — but it works on the fly. Even the upright phone charging slot is about two sizes too small. There’s even a physical ignition key. The simplicity was charming, actually.

Meanwhile, on the other end of the scale, the same off-road upsell makes the Sierra a pretty classy truck, albeit $64,825, including the $995 upgrade for the 26 highway mpg diesel.

I tried to have a civil conversation with a gentleman driving the 2500 heavy-duty diesel version of my still-gargantuan 1500 Sierra, but it appeared he was a drug mule — which explained his jacked-up suspension and blackened windows — so I walked away slowly, left to consider my own truck.

Still, the 1500 AT4 Crew Cab is not small at all, bringing with it big-truck issues such as parking, lane integrity and pedestrian avoidance. But get it out onto a gravel Front Range road in the permanent summer going on down here, and it will fly over snow-melted mud bogs and 2-foot deep ruts, and it provided almost the same level of indestructible fun as that ridiculous Ram TRX.

Better yet, on the highway, and despite its practically square-cornered, tractor-styled, off-road tires and its tall profile and mass, it simply cruised along without any drama. The AT4 suspension tweaks helped make freeway travel non-vomitous, unlike many other extra-big trucks.

Kudos to that quietly powerful turbodiesel engine, with just 277 horsepower but as much torque (460 pound-feet) as the biggest V-8 GMC offers and 23.5 combined mpg. It’ll also pull 9,000 pounds of trailer.

Mine was also the CarbonPro edition, which is not an inside joke about global warming but instead a full carbon-fiber bedliner, which apparently can survive full-speed snowmobile loading accidents.

The Sierra was also my first chance to check out the disco MultiPro tailgate, which flips and flops in various load-friendly configurations and then drops to turn into a step — and also includes a built-in boombox that received its one and only playing of Radiohead in its entire service life.

Andy Stonehouse

Andy Stonehouse’s column “Mountain Wheels” publishes Saturdays in the Summit Daily News. Stonehouse has worked as an editor and writer in Colorado since 1998, focusing on automotive coverage since 2004. He lives in Greeley. Contact him at


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