Here's Why the GMC Hummer EV Is a Misunderstood Raptor Fighter

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Contrast it with the workmanlike F-150 Lightning, and GM's aggro approach to its first electric truck seems odd. But it's all part of the plan.


"An electric Hummer? Really?” Thus went the Greek chorus when the GMC Hummer EV pickup was first teased in a Super Bowl ad in early 2020. Set aside personal taste and objectively, it's hard to imagine a less green vehicle than a Hummer. This is why it's been so very easy to be skeptical of the GMC Hummer EV. So here's what General Motors is doing for its first electric pickup? This six-figure, 9,000-pound, battery-powered thing?

The gambit was bold enough eighteen months ago; since then, the landscape has changed significantly for electric trucks with the buzzy introduction of the normcore Ford F-150 Lightning and the start of production for the friendly-faced Rivian R1T. Both are credible, functional BEV pickups that have generated a ton of excitement without cranking it up to 11. Fair to ask: does that mean GM's aggro-futurist approach is already out of date?

It might—if the Hummer EV was actually aimed at either of those. I'm an automotive engineer by trade, and I recently had the opportunity to lay hands on a prototype truck and take a closer look at how its specifications shake out in person. On the face of it, the Hummer EV doesn’t seem to match up to either the Ford or the Rivian. It’s far more broad-shouldered, to the point of being too wide for some trails; meanwhile, the name itself does conjure up serious off-road expectations. Power is... unreasonable, an estimated 1,000 hp. Its chunky design, high sticker price, painfully-named "Watts To Freedom" max acceleration mode, and almost unbelievable numbers like 16 inches of ground clearance all seem to beg the question of whether GM's actually taking this seriously.

But it is. View it as a halo truck and the logic comes more into focus. More than anything else, the GMC Hummer EV is an electrified Ford Raptor and Ram TRX fighter—decidedly not the electric pickup for everyone, or even most people. And that's exactly the point. Its mission is to generate and capture excitement, and yes, to appeal to buyers who might otherwise consider a street-legal Baja race truck an ideal daily driver. So let's look at how GM set up the Hummer for off-road stardom.

As for the Cybertruck? I'll believe that when I see it.

Three Motors, Two Axles, One Locker​

GMC’s claim of some 1,000 total horsepower results from a combination of three electric motors: one per wheel in back and a single one driving the front. That layout and its corresponding output are almost exactly the same as the Tesla Model S Plaid. GMC’s resulting 3.0-second zero-to-60 mph acceleration estimate is impressive, but that figure is fully 50 percent slower than the Plaid’s claim because the Hummer is a giant box that weighs a rumored 9,046 pounds.

That’s pretty crazy, but if 1,000 hp and 9,046 lbs are the real numbers, then the Hummer EV’s weight-to-power ratio comes out *the same* as the 702-hp, 6,350-lb Ram 1500 TRX to three decimal places: 9.046 lbs per hp. The newly-introduced 2021 Ford Raptor lags well behind with 410 hp, but the upcoming 2022 Raptor R and its unannounced power output might just crush them both in what is currently a much lighter Raptor package.

The Hummer EV should have both of them covered when it comes to launch torque. Direct-drive electric motors make peak torque at zero rpm and produce output so broad there’s no need for a transmission. They’re claiming 11,500 pound-feet at the ground because they haven’t bothered to work backwards to three motor shafts. I took a shot at it using the 13.3-to-1 front and 10.5-to-1 rear axle ratios, and came up with a range of 800 to 1,000 lb-ft. Why the uncertainty? GMC hasn’t shared the relative outputs of the front and rear motors. Doesn’t much matter. The TRX is a distant second with 650 lb-ft of torque. The Rivian R1T is lurking nearby with 908 lb-ft, though.

Unleashing this machine’s 3.0-second zero-to-60 potential requires a launch control mode called Watts To Freedom. Beyond the acronymic name, it’s very similar to the minutes-long pre-launch rigmarole necessary to get the best out of a Model S Plaid. WTF conditions the battery and crouches the air suspension 2 inches below normal before clearing the driver for takeoff. This seems like a tiresome party trick, but it suggests that simple mash-and-go tactics will be more than enough to raise eyebrows in most real-world encounters.

Traction should be of very little concern, whether you’re on pavement or off-road. The twin rear motors will turn at whatever different speeds the computer deems necessary to produce zero scrub on either side, mimicking an open differential. You can also push a button to command a locked rear “differential” and make them run at the same speed. Torque vectoring comes into play in dynamic handling situations, and it’s theoretically possible to drag one side to hasten a pivot turn. Up front, a single motor runs through a standard mechanical differential that feeds both sides, and here the pushbutton actuates an actual mechanical front differential locker.

Hands-On with the GMC Hummer EV​

In person, the Hummer EV is not as cartoonishly massive as you might expect. For one, it’s not nearly as squared off as the Hummer H1—or even the narrower but equally blocky Hummer H2. Ignore the mirrors and the EV’s 86.7-inch overall width is actually 0.2 inches wider than a H1, but it looks far less slab-sided because the doors have some curve to them, its cockpit greenhouse actually has some tumblehome, and both are inset behind flared fenders. Its ultimate width falls between that of the Raptor (86.6 in) and the TRX (88.0 in), which makes all three equally too wide for many brush and rock-lined Jeep trails I frequent.

The Hummer EV pickup only appears wider because it is considerably shorter than the Raptor and TRX. At 216.8 inches long you can forget the crew-cab versions of those; the Hummer is actually 3.2 inches shorter than the stubby extra-cab short-bed Raptor that Ford recently discontinued. But the Hummer does have a crew cab, and its 135.6-inch wheelbase is nearly 10 inches shorter than a crew-cab Raptor or TRX. The result is very short overhangs and far superior approach, departure and breakover angles that give the Hummer EV very recognizable Hummer proportions.

How does a crew cab Hummer EV pickup pull this off? For one, rear legroom isn’t up to the standards of the latest Ram and Ford crew cabs. Also, its bed is 5 feet long like a short-bed Tacoma, not 5-feet 7-inches long like a Raptor’s short bed. The Hummer’s bed does have two offsetting advantages: it is much broader than a Tacoma’s, and it comes with GMC’s Mutli-Pro tailgate. With the load-stop deployed, this tailgate can corral objects that are 6-feet 10-inches long—the same effective length as a GMC Sierra 1500 standard bed.

The stubby rear overhang does create a big problem: there’s no room for a spare underneath. Going off-road without a full-size spare is inadvisable, and we’re talking about a huge, heavy spare. The Hummer EV pickup sits on massive 35-inch LT305/70R18 Goodyear Wrangler Territory MT tires on 8-lug rims. GM wouldn’t talk about the specific spare-tire mounting solution they have in mind, but I can’t see it being anything but a space-hogging bed mount similar to the accessory GM sells for the Chevrolet Colorado ZR2.
 

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Suspension of Disbelief​

Still, it’s hard to argue with very short overhangs, especially when you pair it with a height-adjustable air suspension that has 13 inches of overall front and rear travel. The chosen width of the Hummer EV comes into play here, because you need long control arms to stroke a suspension that much. It’s a similar story with the Raptor 37 (13 inches front, 14.1 inches rear) and the TRX (13 front, 14 rear). The Hummer EV’s rear travel is likely restricted because of its independent rear suspension, but there’s absolutely no differential pumpkin hanging down to snag on rocks.

It’s no surprise that the front employs a double-wishbone setup, but the independent rear also uses double wishbones. It’d have to, if you think about it, to allow for the rear-steer system that can generate as much as 10 degrees of turn angle; opposite-phase action for a tight turning radius (37.1 feet with rear steer, 44.3 feet without) or extreme in-phase motion for the much ballyhooed crab-walk feature.

The Hummer’s air suspension also offers something the others can’t: A full 7.8 inches of height adjustability from the lowest Entry mode to the highest Extract mode. The Terrain and Off-Road modes lift the truck 1.8 inches above standard height, and Extract mode raises it another 4 inches from there. The low-drag Aero freeway cruising height is an inch below standard height, and Entry mode is an inch lower still. Ground clearance is 10.1 inches at standard height, 11.9 inches at Off-Road/Terrain height, and 15.9 inches at Extract height. Corresponding fording depths are 26, 28 and 32 inches.

What’s the difference between the same-height Terrain and Off-Road modes? Terrain is intended for technical low-speed rock crawling, with the accelerator remapped to make it easier to apply in careful increments, and the steering delivering more aggressive rear-steer deployment. Off-Road mode is optimized for high-speed desert running, so the throttle is scaled for heavier applications and the rear steering is used more strategically—presumably tending toward subtle in-phase tweaks for high-speed stability.

Each mode also gets a different adaptive damper calibration, and the dampers are said to be position sensitive so they can firm up more toward the ends of travel and be softer and more compliant in the middle. But the trucks I saw did not have representative hardware, so I can’t say whether or not they’ll have external reservoirs or even the basic beef of Raptor and TRX components. The dampers remain a big unknown, but it’s worth remembering that the Hummer EV’s independent rear suspension may require less elaborate dampers because there’s much less unsprung mass to control.
Suspension articulation is another question. There’s a front stabilizer bar underneath, but the Hummer lacks a disconnect mechanism because the space between the front motor and battery pack is too tight. As for the rear, there’s no stabilizer bar at all. The Raptor and TRX are set up similarly, but I tend to think the Hummer EV may have the ultimate edge. Yes, it has a smidge less rear travel, but its much shorter wheelbase should readily offset that.

What About the Hummer SUV?​

Having said all of this, there is also a Hummer EV SUV. It will come out more than a year later than the truck, so less is set in stone. There are no power or torque estimates to talk about, but they may well be lower because it has a 126.7-inch wheelbase that’s shorter by 8.9 inches. That in turn means that it will have a shorter, lower-capacity battery, and that detail may reduce the amount of power it can deploy. The power of an EV is not always motor limited, but battery limited. It’s why high horsepower versions can paradoxically have more range.

The Hummer SUV’s suspension design and travel will likely mirror that of the truck. But it’s only 196.8 inches long and its rear overhang will be a full 11 inches shorter, so its breakover and departure angles will be far superior. The Hummer SUVs shorter wheelbase will trim the turning circle (with rear-steer on the job) to a paltry 35.4 feet, and it will automatically produce a higher articulation score even if suspension travel doesn’t change one iota. As for the spare tire, it has an obvious and prominent place to live in full view on the rear tailgate.

The more I think about it, the less I’m interested in the pickup and the more I’m drawn to the Hummer EV SUV. It’ll (probably) cost less, fit more places, and be more capable in the way I define that term. But who am I kidding? It’ll still be a wide, heavy and expensive machine. The off-road EV landscape almost certainly will have changed by the time the GMC Hummer EV twins become real. I may well gravitate to the Rivian R1T or R1S, but I’m also anticipating the inevitable all-electric Ford Bronco or Jeep Wrangler. For now, however, it’ll be fun to keep an open mind and see how it all shakes out. This is brand new territory. And what better vehicle to explore the outer limits than a truck?

Dan Edmunds is a veteran automotive engineer and journalist who worked in vehicle development for Hyundai and Toyota specializing in chassis tuning. He was also the director of vehicle testing at Edmunds.com for 14 years.

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