Review: 2024 GMC Hummer EV SUV shows off what can be

The 2024 GMC Hummer EV SUV is a show off. The 9,000-pound beast sprints to 60 mph in 3.5 seconds. It has an air suspension that can adjust the ground clearance by 9.7 inches. Its rear-wheel steering has a Crab Walk feature that enables it to move diagonally. And it has video game graphics with a lunar theme because this terrestrial machine has yet to meet its planetary match. 

So we’re told. Even for one of the world’s most off-road capable passenger vehicles, the Earth remains an undefeated opponent. Due to record rainfall splashing on the dusty heels of a record drought in the central coast of California wine country, GMC was unable to show off the full capability of its second and more accessible Hummer EV offering, the 2024 GMC Hummer EV SUV. 

It’s a bizzaro world, where floods overrun droughts, and a gas-guzzling tactical military vehicle repurposed for civilian life has been resurrected as the halo car as one of the world’s largest automakers pivots to an all-electric future. 

Unlike the Hummer EV truck that launched in 2022, the Hummer EV SUV looks much more like the Hummer H2 that flaunted its excess in the early part of the Millennium. It’s squat and wide, with a smooshed greenhouse and brawny fenders that bulge over 22-inch wheels. It’s an American bulldog. 

But GMC neutered the rear of the SUV compared to the Hummer EV pickup. The wheelbase is 8.9 inches shorter, and it’s 20 inches shorter in length. That results in a smaller 170-kwh battery pack, with 20 modules stacked 10 and 10 instead of the 24-module setup of the 205-kwh pack in the truck. From the C-pillar forward it’s the same as the pickup, but with the rear wheels pushed toward the swing gate and its full-size spare. It looks more proportional than the truck, and it’s better to fit into garages, and to clamber off-road. Allegedly. 

GMC shuts down Hummer EV SUV off-road course

It was raining when we arrived in Napa, and it was raining when we left. The San Franciscans rejoiced that the drought-depleted reservoirs had refilled in just three months of rain. But the saturated soil compounded an underlayer of ash from widespread forest fires in 2020 to make the earth unstable, toppling trees and encouraging landslides. It squished underfoot.

“It was like mashed potatoes,” Sean Poppitt, director of global Buick and GMC communications, said about the conditions.

The day before we arrived, a Hummer EV SUV got stuck six minutes into a trial run up a steep incline on a hillside. Despite recovery hooks and winches on other Hummer EVs, the team needed a Bobcat for its four-hour recovery. Bear in mind, the SUV is the better off-road version of the Hummer EV. It has nearly the same approach angle as the Hummer EV truck (49.6 degrees in the SUV vs 49.7 degrees), but an improved breakover angle of 34.4 degrees (32.2 in the truck) and the stubby end makes for a much friendlier departure angle of 49 degrees (38.4 in truck). 

As Plan B, GMC created a flatter off-road course showcasing the Hummer EV SUV’s capability. The heavy rains had turned the field into a mush akin to ride paddies, with the 8,700-pound Hummer EV SUV sinking if it stood still. (GMC could not confirm the curb weight of the Hummer EV SUV by press time.) We could only ride along with GMC experts, such as Aaron Pfau, the GMC Hummer EV lead development engineer. In spite of or because of the conditions, he showed off just how much the Hummer EV SUV is a show off. 

2024 GMC Hummer EV SUV digs out of mud

Pfau turned the drive mode dial on the center console to Terrain mode, and the air suspension raised the ground clearance from the standard 10.1 inches up to 11.9 inches. The three permanent-magnet synchronous motors began to deliver max torque at low speeds. The single motor up front and twin rear motors apportion up to 1,200 lb-ft of torque based on individual wheel speed, so it was much more precise and reactive than the low gear of a 2-speed transfer case. An electronic locker up front and a virtual locker at the rear can lock across each axle, and the front and rear can be locked together. All four wheel speeds are constantly measured and adjusted.

Terrain mode dislodged the Hummer SUV EV from mud that climbed about halfway up the 18-inch wheels spiked with knobby 35-inch Goodyear all-terrain tires. On deep muddy turns it took some work from the rear-axle steering to stay on course, but overall there was no need to engage Extract mode as they had to do the day before on the hillside; that raises the ground clearance to a max of 15.9 inches.

Crab Walk might have been the biggest show off. Using the rear-axle steering that turns the rear wheels up to 10 degrees in phase with the front wheels, the Hummer EV SUV scrabbled diagonally up and down the banks of a mud pit that was essentially a half of a halfpipe. Activating it required a press and hold of the left side of the console dial until the Crab Walk icon appeared on the touchscreen. After it dinged, an underbody camera view appeared. Two cameras, one in the center behind the front axle and another at the rear axle, have built in washers that were more than necessary. They enabled us to see what we were driving over, which was a whole lotta mud. In total, 17 different camera projections give eyes where spotters can’t go, and help to see out and over the broad hood and narrow windshield. 

Other vehicles have less sophisticated systems to help with off-roading, like Ford’s that locks the inside rear wheel so it essentially gets dragged around a narrow turn. The Mercedes-Benz EQS SUV has rear-axle steering that also enables sharp pivots around tight corners. Crab Walk is next level. Moving diagonally was an odd sensation, in a parking lot or in the mud. At about 180 degrees of steering wheel input, it surpasses the 10-degree threshold of rear-axle steering, so if you keep turning the steering wheel it will actually turn, but not with the same tight turning circle of 35.4 feet if it were in Normal mode. It automatically disengages at speeds over 15 mph.   

The UltraVision camera system, front e-locker, and AT tires are part of the $10,000 Extreme Off-Road package (on the 3X trim; it’s $5,000 on the Edition 1) that includes five steel skid plates running from the front bumper to the rear axle and sealing off the stacked battery pack. With no locking differential hanging down like a dangling pumpkin, the flat underbody created plenty of space to clear rock and log obstacles. The mud bath seemed welcome, with the man-made lagoon water rising up to the Hummer letters on the grille, nearing the max of its 32 inches of water fording capability. 

The front locker can be manually engaged with a long press of the locker button on the panel below the touchscreen (and it will automatically disengage over 25 mph), but Pfau said nine times out of 10, it’s not necessary because the modes take care of it. The five modes, including a My Mode setting, all have a different style of lunar graphics that are as sharp as PC gaming graphics. The modes affect the steering, alter the damping, tweak the traction control settings, and adjust drive noises in the cabin. 

“It’s taking the native drive unit sounds and amplifying the sounds we want and layering a blending of sounds to communicate the power and torque,” Pfau explained. “Each mode has their inspirations for sound.”

The sound can also be shut off. 

Unfortunately, due to the deluge, we didn’t test the Off-Road mode, which essentially acts as a higher speed Baja-type mode. It drops the air suspension down to the Normal setting, turns down the traction control setting, and the torque shifts more to the rear axle to allow for a greater yaw rate and let the big blocky tail whip. Shutting off traction control completely essentially makes for a Drift mode. 

Hummer EV SUV WTF rips

The last mode available in the 2024 GMC Hummer EV SUV’s propulsion arsenal is Watts to Freedom, or WTF. The inspiration for the amplified sound of this mode was the Formula E electric racing series. 

To activate it, double tap the traction control toggle, then confirm Watts to Freedom in the instrument cluster. The air suspension lowers 3.54 inches, or from 10.1 inches to about 6.5 inches of ground clearance, which is lower than the entry/egress setting. The wheel gaps disappear, the bulldog squats on its haunches, the seat vibrates to remind you of what’s happening, and the dampers go to full firm. The steering wheel must be straight. Once lowered, press and hold the brake, hammer the accelerator, and let go of the brake.  

The nose raises as this block of an SUV shuttles forward, pinning you in your seat. It uses all three motors but initially retards front motor torque. Keeping the wheel straight is a challenge. It’s remarkable and unsettling, to be sitting so high and moving from 0-60 mph in 3.5 seconds (3.0 in the truck). The Hummer EV can be kept in that WTF for however long you want, but it is not advisable due to the bottomed out suspension. But it is a neat party trick.  

Everyday in the Hummer EV SUV

Around town, the Hummer EV SUV casts a large presence on the road. It’s so wide it requires three amber lights up front like heavy-duty trucks and commercial vehicles. Congested urban roads can cause concern. The greenhouse is so squat, and the windshield so broad and narrow that it requires three small windshield wipers to clear away rain. It can’t come with a head-up display because there would be nowhere safe to project it. 

The staggered screen layout, with a 12.3-inch instrument cluster side stepping into the 13.4-inch touchscreen eats up some visual space. The screens are simple to use with excellent graphics that show everything from which wheels are getting torque to the altitude to the pitch and yaw rates. The graphics and interface herald great promise for what may trickle down into lesser GM electric vehicles. 

Another big plus is the fact that the drive mode and climate functions are not relegated to the touchscreen. A console dial controls drive modes and suspension height, and a smart climate bar with actual toggles operates the HVAC. It looks and feels like a classic truck, while still progressing fully into the next generation of automotive. It’s really well done. 

The Hummer EV SUV is roomy up front, but the narrow windows and chunky A-pillars limit outward vision. The three seats in the back have less room, especially for knees. Four adults will fit fine but the rear passengers may not be up for the longest trips. 

Drivers sit high and ride high, and even with active dampers and air springs at each corner, it leans into turns like a boat. The knobby AT tires get rubber ducky loud above 60 mph, and wind noise thwomps the side mirrors and pillars. At speeds under 50 mph, it’s mostly quiet. 

I tested both the 2024 Hummer EV 3X SUV for $106,645, including a $1,995 destination fee, and the sold out Edition 1 for $105,595. In June, GMC stopped taking reservations for the Edition 1 SUV, and GMC jacked the price by $6,250 for EV3X, EV2X, and EV2 models. The testers were similarly equipped, with a $1,495 Infinity Roof on the EV3X with a spine down the middle and four detachable panels that can be stowed neatly in the frunk. 

The Edition 1 came with the latest iteration of Super Cruise, GM’s excellent hands-free driving system now usable on more than 400,000 miles of limited-access highways. I had intermittent access on Highway 101, however, and couldn’t figure out why. The lanes were clearly marked, it wouldn’t activate even outside construction zones, and it wasn’t an off-road model with gunked up sensors. When it was enabled, it kept the lanes well, maintained speeds, and executed a lane change without driver intervention. Still, the giant size of the Hummer EV SUV prompted me to keep my hands close to the wheel. 

2024 Hummer EV SUV charging

Like the Hummer EV pickup, the SUV uses a stacked battery pack that mostly runs in parallel and then switches to series for 800-volt DC fast charging. At a station that can pump out 300 kw, the Hummer EV SUV recoups 100 miles or range in about 14 minutes. GM estimates most public DC fast charges will deliver only 117 kw, however, so it would take 55 minutes to charge from 20-80%. Such are the drawbacks of a 170-kwh battery pack. 

I didn’t test charging, but I did test the efficiency to the tune of 1.4 miles per kwh over 90 miles of Highway 101 and rural roads. That’s about half of what you might expect from a typical crossover EV, or worse. The climate control was off, and it climbed 950 feet but descended the same amount. I used the one pedal regen brake setting on the steering wheel paddle, but it was erratic and jerky in such a large vehicle. It was smoother to use the L setting in the shifter, and I could’ve dialed up different regen settings in the touchscreen. Having three different places to adjust regen was overkill, but I expect owners will find and keep their preferred setting, then use the one-pedal paddle in certain situations. 

New for 2024 on both the SUV and truck, a 19.2-kw onboard charger for faster 240-volt charging times comes standard on all but the base EV2. It recoups 30 miles an hour, and takes about eight hours to charge from 20% to full. Keep in mind, it requires a 100-amp circuit, so older houses may require an electrical upgrade. 

The coolest thing about it, however, is that it enables vehicle-to-vehicle (V2V) charging at 6 kw to any electric vehicle with a SAE J1772 five-pin connector. GMC wouldn’t disclose the cost of the adapter at press time, but in a demo, one Hummer SUV charged another Hummer SUV at a rate of nine miles an hour. 

The onboard charger upgrade marks a big change in a short amount of time since the 2022 GMC Hummer EV truck debuted with an 11.5-kw onboard charger. The “old” trucks can receive a jump, so to speak, but they don’t have the capacity or hardware to charge another electric vehicle.

Both versions of the 2024 GMC Hummer EV also gain vehicle-to-load (V2L) power generation through GMC’s Power Station generator that can provide 3 kw to power tools, camping equipment, home appliances, an air compressor, or other needs with a 120-volt connection.

GMC Hummer EV SUV availability

GMC expects the SUV to account for at least 60% of Hummer sales. In this sense, the Hummer EV SUV better reorients the entire GM brand on its pivot to becoming an electric vehicle automaker. 

The six-figure halo models are intended to drive excitement for GM’s Ultium propulsion system strategy on more accessible, less expensive vehicles to follow, including the eventual arrival of base Hummer EV trucks and SUVs. Next up are the fleet version of the Silverado EV, followed by the Blazer EV, the Equinox EV, the Silverado EV for retail customers, then, in 2024, the GMC Sierra EV.

It’s all about the buzz, and it appears to be working, with GMC halting reservations in September after 90,000 reservation holders raised their hands. It’s impossible to predict how many will become buyers, and GM won’t disclose production numbers, but the first 2024 Hummer EV SUVs should be delivered at the end of the month. 

Yet the strategy to sustainability remains a head-scratcher. Both Hummer EVs are as inefficient with electricity as the H2 was with gas. Then there’s the painful irony we experienced. That an earth conquering military-inspired vehicle repurposed for an electric age amidst the swirl of climate change should have trouble tackling the very manifestation of that climate change is a sober reminder: the Earth wins. GM’s concession to this reality remains defiant.   

But the Hummer EV SUV remains an impressive showcase of GM’s EV technology. We’ll see what trickles down to more accessible, sustainable vehicles.  

GMC paid for lodging and airfare for Motor Authority to present this firsthand report.

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