2027 GMC Sierra AT4X First Look: 35s, Lockers, and a Hidden Glove Box
GMC has completely reinvented its half-ton lineup for 2027, and the off-road flagship is no exception. I got up close with the next-generation 2027 GMC Sierra AT4X at the GMC booth at the State Fair of Texas in Dallas. At first glance, it looks familiar. Look closer, though, and this truck is packed with smart upgrades, from bigger tires to a glove box hiding behind the screen.
The AT4X starts at $85,495, including destination. That’s only $2,400 less than the range-topping Denali Ultimate, and you can see how it compares with the rest of the lineup in our 2027 GMC Sierra 1500 specs and pricing breakdown. Like the other trucks at the fair, this one was parked in show mode, so I couldn’t drive it. Here’s what stood out.
A Familiar Face With Off-Road Upgrades
Up front, the new Sierra is more evolution than revolution. You still get a big, bold GMC grille, complete with an AT4X badge tucked into the corner. The question-mark-style headlights and running lights are borrowed from the Sierra EV in an updated form. Meanwhile, the fog lights sit low in a reworked bumper that gives the tires more clearance.
Look below the bumper and you’ll spot red tow hooks. On the AT4X, they’re mounted horizontally instead of vertically like on the other trims. GMC made that change to free up more underbody clearance. There’s also plenty of metal protection underneath, which makes sense for the most capable Sierra in the lineup.
The display truck also had an engine block heater, which is a nice touch for buyers in colder climates.
Bigger Tires, More Lift, and Your Pick of Power
The AT4X gets a factory 2-inch lift, and for 2027 it rides on proper 35-inch tires. The outgoing truck wore 34-inch rubber. This one gets Goodyear Wrangler Territory MT tires in a 285/75R18 size, wrapped around dark 18-inch wheels. They sit under new octagonal wheel arches trimmed in black cladding.
GMC pairs that lift with Multimatic DSSV dampers and electronic locking front and rear differentials. For the trail, you also get 360-degree cameras, and the Sierra lineup offers available underbody cameras. Every Sierra gets a trailer brake controller, and the AT4X adds a two-speed transfer case. Out back, GMC sticks with a traditional leaf-spring rear suspension.
On the 2027 GMC Sierra AT4X, the 3.0-liter Duramax turbo-diesel inline-six is standard. Our display truck had the available 6.6-liter V8, the most powerful engine in the Sierra 1500 lineup at 481 horsepower and 501 lb-ft of torque. You can see which engines come on which trims in our Sierra 1500 engines by trim breakdown. An even tougher AT4X AEV Edition is also on the way, with more underbody protection and different wheels.
A Leather-Free Cabin That Still Feels Premium
Step inside, and the AT4X feels like a luxury truck built to get dirty. The materials are soft and premium, but there isn’t a stitch of leather here. GM dropped real leather from the entire 1500 lineup for 2027. GMC uses a synthetic alternative, but it doesn’t give the material a special name.
The front seats offer massage, lumbar, and bolster adjustments, plus two-person memory. Bose speakers are built into the headrests. On the door, a single touch panel handles the locks and mirrors, and the truck knows exactly where you press.
I asked plenty of fairgoers about this same leather alternative in the Chevy Silverado High Country. Not one of them called it a downgrade, and nobody said it would keep them from buying the truck.
Since the AT4X is lifted, climbing in takes a little effort. Our truck didn’t have running boards, but A-pillar grab handles help. Keyless entry also works on all four doors, as long as the key is on you.
The Back Seat
The back seat gets the same soft materials as the front, including two-tone seatbacks. It’s a big step up from the stiffer leather in older GMC trucks. Rear passengers also get heated outboard seats, air vents, rubber and carpet floor mats, and several USB-C ports.
My favorite trick is under the seat. The 60/40 cushions flip up without any latches or levers, so you can grab something from underneath without walking around the truck. One downside is the floor. A tunnel runs through the middle, while Ram and Ford offer flat load floors.
Smarter Screens and a Hidden Glove Box
The driver faces a new steering wheel with touch-sensitive panels instead of traditional buttons. It’s a cost-saving move, but it beats burying those controls in a screen. Below the screen, gloss black buttons control the two-speed transfer case.
Every Sierra gets a 16.3-inch center touchscreen, and the new home screen is a highlight. You can run Apple CarPlay in one pane and customize the side panel. Better yet, you can keep a map like Waze in full screen while your audio controls stay on the side. That means you can report a stalled car without losing your music controls.
Here’s my favorite GMC trick. Press a button and the big screen moves up and out of the way, revealing a hidden glove box. The truck must be on for it to work. Chevy doesn’t offer this, and Silverado buyers who add the passenger display give up the secondary glove box.
The passenger screen is highly polarized, so the driver can’t see it. It can stream YouTube, Disney+, and more through the truck’s built-in connection. You also get a head-up display, a rearview camera mirror, and the first panoramic sunroof on a full-size GMC pickup.
A Console That Turns Into a Workstation
Moving the shifter to the steering column freed up room in the center console. It slides, passes through to the back seat, and flips forward into a workstation. You can even hide a laptop underneath it. There are two magnetic wireless chargers, plus USB-C and HDMI ports on the side so you can plug in an Apple TV or Fire Stick for the passenger screen.
My one gripe is the gloss black. It’s on the doors, the center stack, the console, and even on the back of the center console. Let us know what you think of it in the comments.
A Smarter MultiPro Tailgate and a Heated Sliding Window
Around back, the AT4X gets clear tail lamp lenses, a GMC detail that sets it apart from the red lenses on the Chevy Silverado. You also get corner step bumpers and a spray-in bedliner with plenty of tie-down points.
The MultiPro tailgate has re-engineered buttons. One opens the full gate, while a second, bar-shaped button opens the smaller upper section. From there, the upper gate works as a load stop, a workstation, or a step, and it has a built-in ruler for measuring your catch. You can also add a Kicker Bluetooth speaker system for tailgating.
GMC also listened to owners worried about dinging the tailgate on a trailer hitch. A new safety lockout in the infotainment system makes you press, hold, and acknowledge the hitch before both sections drop. There’s power in the bed, too. However, unlike the Ford F-150 PowerBoost, it can’t serve as a generator.
Finally, the sliding rear window is now one piece of glass with an opening cut into it, much like Ford’s. That lets GMC add a heating element. Previously, you had to give up a heated rear window to get the slider.
Final Thoughts on the 2027 GMC Sierra AT4X
The 2027 GMC Sierra AT4X doesn’t reinvent the look, but nearly everything you touch has improved. The 35-inch tires, the hidden glove box, the flip-forward console, and the heated sliding window add up to a smarter off-road truck. I’d still like to see less gloss black inside.
If you want even more capability, the AEV Edition is coming soon. Until then, check out our 2027 GMC Sierra AT4 first look and Sierra Denali first look to see how the rest of the lineup compares.