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Hummer is back with a truck that is even bigger and badder than the old gas-fuel iteration, the uber off-roader inspired by the original Army Humvee.
But this time around the Hummer EV Pickup is a 1,000-horsepower, 9,200-lb. monster that packs a double-stacked 205-kilowatt-hour lithium-ion battery pack. The incredible power of the Hummer’s triple Ultium electric motors provide a 3.0-second 0-60 mph time, while the computer-controlled air suspension and active shock absorbers lend the Hummer EV an unexpected combination of agility and plush comfort on the road.
It achieves this incredible performance while delivering an EPA miles-per-gallon equivalent (MPGe) of 47, which is approximately equal to the 49 mpg EPA rating for the all-wheel-drive version of the hybrid-electric Toyota Prius.
Of course, the point of the shift to electric drive is to exceed the efficiency of hybrids like the Prius. And GM will do that with its new Ultium battery and drivetrain strategy—just not with the Hummer EV Pickup. The company is launching its onslaught of 30 new EVs by 2025 worldwide, all of which will employ portions of the modular Ultium building blocks that are used in their maximum configuration in the Hummer.
That’s the purpose of the massive truck: To demonstrate the ultimate capability of the technology in a halo vehicle that it can build at a measured pace and sell for a high price, while the company’s EV production matures toward the high volume and affordable price of future models that use smaller batteries and fewer electric motors.
“[Ultium] is the platform that allows us to accommodate the future technology development, reduce costs, and speed up the technology development process,” explained Mei Cai, GM’s director of battery cell systems research in the Hummer EV documentary, Revolution.
“It will be the driver for us to expand the EV platform,” she said. “Ultium is the key for our all-electric future.”
It’s a beast
The 24 battery modules of the Hummer EV Pickup’s Edition 1 configuration ($112,595 as tested, with lesser versions available in 2024 with a starting price of $82,000) weigh more than 2,900 pounds and contribute to a 9,063-lb. curb weight (according to GM’s EPA filing) for a 329-mile driving range. But other GM vehicles will use fewer modules for lower weight and cost.
A key advantage of EVs, even ones like the Hummer EV whose efficiency is no better than that of existing gas-fueled hybrids, is that the source of their electricity is the ever-greening power grid. That means that in some places they can already be charged by renewable sources, and such sources will become increasingly available throughout the vehicle’s life, while the Prius will burn gas until the day it goes to the big junkyard in the sky.
GM underscored this point by charging all of the Hummer EVs at the media drive event from its Hydrotec mobile fuel cells using renewably produced hydrogen.
You’d never know the Hummer weighs so much, thanks to its agility and the smooth ride afforded by the truck’s air suspension and off-road balloon tires. With GM’s Super Cruise driver assistance taking over on the highway, the Hummer is even more relaxing to drive. As for parking, well, it is still more than 18 feet long and fills a space from the right-side line to the left one.
Rear-wheel steering
Lining the Hummer up to make sure it is straight enough to squeeze into the spot is eased by the rear-wheel steering system, which was developed primarily to aid the truck’s off-road maneuverability. With a four-door cab and a bed, the Hummer would be challenging to snake around trees and other typical off-road obstacles, but the rear steering lends it the feel of a two-door SUV.
The rear-steer system also communicates with the truck’s stability control system to provide advanced trailer sway control. The rear steering is handy, too, for ease of parking, but the technology’s party trick is the Hummer’s CrabWalk: It can slide sideways with all four wheels pointed at the same angle. This could potentially be used for parallel parking. Or for easing past obstacles in the outback. But it will probably be used mostly to show off the gimmick to friends.
Off-roading
In addition to having rear steering to help swerve around trail obstacles, the Hummer EV also has precise control of its electric power delivery, electric regenerative braking, and friction braking to help the truck climb over obstacles. Careful application of power to the wheels with available traction is vital, but controlling wheel speed while rolling down the back side of obstacles also required significant engineering effort.
“We had to balance torque placement and slip control, which allows you to confidently climb up a rock or ledges,” says vehicle dynamics engineer Drew Mitchell. “We also use the brake controller to apply mechanical brakes to give you that left-foot braking sensation without actually using the brake. It is all one-pedal control.”
Experienced off-roaders know to gently apply the brake with their left foot to control speed so the truck does not come crashing down off the downslope of hills or the back side of rocks and logs. Hummer engineers aimed to provide that for inexperienced drivers too.
Meanwhile, one-pedal driving is a typical EV driving option, and the Hummer EV can drive in that mode. That’s when the vehicle operates like a golf cart, where stepping on the gas pedal makes it go and lifting off makes it stop, thanks to regenerative braking. But for off-roading, the Hummer’s version goes beyond that, letting drivers control the vehicle’s progress to the inch using only the accelerator pedal, just as the gas-powered Ford Bronco’s similar system does. “It is not [typical] EV one-pedal drive, which we have in all the other modes, the traditional EV solution,” says Mitchell. “This is a one-pedal drive where you are coming off the accelerator, the brakes grab and it gives you that immediate deceleration.”
“We tried to make it as approachable for novices as possible,” says Mitchell. “A lot of people, the first time they go off road, left-foot braking can be a very jerky affair. You can still left-foot brake the truck if you want. It is a slow, gradual stop. We also have a more aggressive one if you put it in Low range.”
The result is as good as promised, with the Hummer easily oozing down obstacles with just the right foot on the accelerator.
The drivetrain
The Hummer’s electric drivetrain is laid out with a single front electric motor that sends power through a lockable differential to the front wheels. There are also dual rear electric motors, each driving one wheel. These motors can be synchronized to simulate a locked differential, so that both wheels turn at exactly the same rate.
During the trail drive, after seeing the Hummer ahead of me work a little bit to climb a rock scramble, I preemptively locked the rear differential (virtually), and my truck crawled up the same section with zero drama.
And that’s really the Hummer EV’s bottom line: no drama (other than when demonstrating CrabWalk mode to onlookers). There’s no drama while driving it on the highway because it is as comfortable and smooth as on-road-oriented vehicles. There’s no drama off-road because the Hummer EV is stupendously capable. And there’s no drama at the gas pump, or at the charging station, because the Hummer EV has a prolonged 329-mile driving range, fast 800-volt DC charging, and sufficient electric efficiency to put this bruiser on par with Prius for Earth-friendliness—at least when comparing the new Hummer’s MPGe with the Prius’s fuel efficiency.
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