So you think GMC is drawing a bead on the Ford F-150 Raptor? Think again. What we have here is more like GMC’s attempt to build the Range Rover of pickup trucks.
The Sierra AT4 is targeting a subset of pickup drivers who, GMC believes, want “authentic off-road capability and innovative technology paired with premium refinement.” Making its debut on the all-new 2019 Sierra, AT4 is also a sub-brand that will extend to the full GMC lineup over the next two years.
The “premium” part should be already baked in, since that’s the Sierra’s brand shtick within the wider pickup universe. The off-road part is added on, and comprises a two-inch suspension lift, AWD with two-speed transfer case, locking rear differential, off-road-tuned monotube shocks, skid plates, hill-descent control, terrain select, and all-terrain tires.
For hardcore boonie-bashers, available SurroundView provides an up-close view of that boulder before you hit it (although a reasonably high driving position is possible, what you mostly see up front is the towering mass of the hood); and a colour head-up display that can show tilt angles.
Also available is a performance package that adds freer-flowing intake and exhaust plumbing to liberate an additional 15 horsepower and 9 lb.-ft. of torque from the available 6.2-litre V-8 (a 5.3-litre V-8 is standard, while a 3.0-litre diesel is in the pipeline for next year). You can have your AT4 in three shapes: double-cab long-box, and crew-cab short- or long-box.
Let’s say it right now: no vehicle stretching six metres from stem to stern, and on a wheelbase pushing four metres, can claim ultimate go-anywhere talent. In some off-road scenarios, a full-size pickup is Just. Too. Big.
Still, the AT4s were unfazed by the obstacles and terrain provided for our sampling by GMC, including deep sand and a slope strewn with boulders the size of basketballs. Even when we were being tossed by the turbulence of the terrain, the underside kept clear of the rocks below. (Minimum ground clearance is a lofty 10.8 inches.)
A more telling example of the AT4’s clearance limitations was the garnish of mud and grass scooped up in the recovery-hook apertures of the front bumpers.
Still, even legit off-roaders will spend most of their AT4 drive time on pavement. That’s what I did, too, tackling a mix of rural two-laners, small towns and (mostly) freeway. In those environments, where the sheer size of a full-size pickup isn’t a handicap, the AT4 is very easy to like. It drives small, thanks to light steering that remains remarkably precise even on the test trucks’ optional mud-optimized all-terrain tires.
I’m almost tempted to call the steering “delicate.” And if that suggests a lack of manliness (on the truck’s part), GMC spokesperson Jennifer Ecclestone reminds me that most new customers are former car and CUV drivers who wouldn’t want "heavy-duty” steering. They will also appreciate that there’s nothing heavy-duty about the ride, either.
If you want to strut some machismo, just option your AT4 like my test truck, with the brawny 6.2-litre V-8 and Performance Package. While the effect of 15 extra horsepower (stock is 420) may only be obvious to a stopwatch, there was no missing the classic all-American V-8 rolling thunder emanating from the tailpipes.
There’s nothing wrong with an, um, assertive V-8 in a full-size truck, but is it consistent with the AT4’s mandate of “premium refinement?” OK, so you don’t have to pick the 6.2 or the Performance Package. But there’s another contradiction between the “premium” pitch and the reality: the AT4-specific interior furnishings – all-black, apart from darkened aluminum trim accents, French stitching and Kalahari inserts on the seats – don’t add much in the way of obvious premium-ness.
And then there’s the wall-to-wall rubber mats on the floor. GMC may talk premium refinement, but above all else, this truck was designed to get down and dirty.
- Base price: $61,500
- Engines: 5.3-litre V-8, 6.2-litre V-8, 3.0-litre L-6 turbo-diesel (late)
- Transmissions/drive: 8- or 10-speed automatic/2-range AWD
- Fuel consumption (L/100 km): Not available
- Alternatives: Chevrolet Silverado Z71 Sport, Ford F-150 Raptor, Nissan Titan Pro-4X, Ram 1500 Rebel, Toyota Tundra TRD Pro
The unique AT4 wheels are modest 18-inchers to accommodate all-terrain rubber, but 20-inchers are available. Other cues (apart from the 2-inch suspension lift) include vertical red recovery hooks and a black body-colour grille surround with black mesh insert.
It’s a steep climb up into the cab, but assist steps are available – even on “off-road” versions. Once inside, the predominantly black, rubber-floored ambience seems more utilitarian than premium, but comfort is easy to find at the wheel, and the crew cab claims best-in-class legroom. The only available screen size is an 8-incher – which leaves ample room for real radio and HVAC knobs and buttons – and the main instrument cluster even includes oil-pressure and battery voltage gauges.
Even with the optional Performance Package, the optional 6.2-litre V-8 isn’t as potent as the Ford Raptor’s 3.5 turbo V-6, but it should be the second-quickest full-size pickup out there (0-60 mph in 5.8 seconds according to Motor Trend magazine, for the stock engine, in unfavourable testing conditions). And hey, it’s a V-8 – and it sounds the part.
Bigger screens are available elsewhere, but the AT4 has the connectivity you’d expect, including 4G LTE WiFi hotspot capability. A head-up display and rear-camera mirror are segment firsts, and SurroundVision is an off-road bonus. Driver-assist and autonomous safety technologies are up to par, with one surprising omission – there’s no adaptive cruise.
GM’s redesigned pickups claim the largest boxes in the segment, and GMC adds its unique MultiPro Tailgate featuring six unique functions, including a built-in step. Later in the model year, a carbon-fibre bed interior will be offered. A trailering package (with 2-inch receiver and 7-pin electrics) is standard, as is the ProGrade trailering system with hitch guidance and in-vehicle trailering app.
The verdict: 8.0
Capable off-road and great to drive on-road, but the Sierra’s interior lacks the claimed premium refinement.
The writer was a guest of the automaker. Content was not subject to approval.
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