As we found ourselves pointing down the treacherous Johnson Valley trail known as the backside to Chocolate Thunder, the one thing going through our minds was “there is no reason we should be on this trail, with this truck.”
Yet, there we were, in the middle of King of the Hammers territory, piloting a massive 2024 Chevrolet Silverado HD ZR2 Bison down a trail that no owner in their right mind would ever find themselves traversing on purpose.
This says a lot about the confidence the Chevy team has in the new crew-cab-only Silverado HD ZR2 Bison and the newfound capability that comes with the HD ZR2 package, but at a price that is dangerously close to touching six figures with AEV-equipped diesel models (our tester rang the bell at just under $96,000), we knew this exercise was more about showing off an extreme use case that most customers will never appreciate.
The fact that the truck had the chops to get us through the rocky obstacles unscathed was a testament to what went into the development of the Silverado HD ZR2 Bison trucks.
Bison, of course, is what Chevrolet uses to indicate a collaboration with upfitter American Expedition Vehicles and AEV has been making quite a name for itself lately in the GM world. Once only synonymous with aftermarket builds sold through Jeep and Ram dealerships and OE-quality upfitter parts, AEV’s partnership with GM is more than just a typical licensing agreement.
All AEV parts are designed and manufactured by AEV for GM and installed on the assembly line at the time the vehicle is manufactured. The amount of work that has gone into making these products integrate into both the OE design and manufacturing is a feat worthy of its own story.
With the introduction of the Silverado HD ZR2 Bison, Chevy finally has a true competitor that matches up favorably against the Ram Power Wagon, Ram Rebel HD, and Ford Super Duty Tremor. As a note, the Tremor is the sole truck amongst this lot available in a one-ton configuration.
Chassis
General Motors has the only heavy-duty truck platform that uses an independent front suspension (IFS), as Ram and Ford both have solid axle setups. GM has maintained that the benefits of IFS outweigh the negatives, yet they have never maximized the platform to take advantage of those benefits. Previous generations of the truck have been hampered by harsh and unforgiving ride quality and inferior dampers.
Turning the page to the 2024 ZR2 model and all of this has changed, thanks to upsized Multimatic DSSV damper technology from the Colorado ZR2, which, along with unique control arms and knuckle geometry, transforms the heavy Chevy into a truck that no longer feels like driving an empty dump truck on the trail.
The shocks, along with the 1.5-inch suspension lift and the addition of aggressive 35-inch Goodyear tires, completely transform the personality of the Silverado HD to something you actually want to take offroad. Other upgrades include a rear locking differential and a full-size spare. It’s great to see Chevy stepping up its game in such a significant way.
You can turn any Silverado HD ZR2 into a Bison by checking off the appropriate order box. For $9,135, the Bison trim adds a high-clearance AEV stamped steel and winch-ready front bumper, a high-clearance AEV rear bumper with heavy-duty cast iron recovery points, stamped steel skid plates (engine, steering rack, transfer case, and exhaust), along with five gloss black AEV wheels (the spare is matching), badging, interior trim, 36-gallon fuel tank and a two-tone Multi-flex tailgate.
Powertrain
Engine choices consist of the 6.6L gas V-8, which is rated at 401 horsepower and 464 lb-ft of torque and the 6.6L Duramax turbo diesel V-8 which makes a tire dissolving 470 horsepower and 975 lb-ft of torque. Both engines are teamed with 10-speed automatics. By comparison the Power Wagon’s sole engine choice, the 6.4L Hemi V-8, is good for 410 horsepower and 429 lb-ft of torque and the 6.7L Cummins I-6 turbo diesel Ram Rebel HD puts out 370 horsepower and 850 lb-ft of torque.
On the Ford side, the Tremor can be had with the 430 horsepower and 485 lb-ft of torque 7.3L gas V-8 or the impressively healthy 475 horsepower and 1050 lb-ft of torque 6.7L Power Stroke V-8. The Rams get an 8-speed automatic on gas trucks and a 6-speed automatic on diesel trucks, while the Ford backs both engine choices with a 10-speed automatic.
Styling
We consider this mid cycle refresh of the Chevy HD trucks to be one of the more successful in recent memory. The company successfully toned down the controversial frontend styling of last year’s truck and refined the looks with a handsome update. Add to that the high-clearance stamped bumpers from AEV and the Bison trucks look stout, muscular, and ready for whatever you can throw at them.
Interior
The interior update, shared with the HD’s half-ton Silverado 1500 sibling, brings the Chevy’s interior up to a competitive level with others in the class. It features more premium materials, an improved layout, all of the latest tech, and a massive 13.4-inch center screen with a configurable 12.3-inch driver information center.
An available 15-inch Head-up Display keeps the driver’s view in front of them and not on the dash. Bison models enjoy some additional AEV branding, such as an embroidered logo on the headrests and the interior textiles were chosen with easy cleanup after a day in the dirt, in mind.
Capability
Heavy-duty trucks have a primary mission that doesn’t necessarily include off-roadability as a top discipline, so it’s good to know that the Silverado HD ZR2 Bison is up to the task of work. Gas-powered ZR2 Bisons are rated to haul up to 3,013 pounds in the bed and diesels top out at 2,811 pounds. By comparison, Power Wagon can haul 1,660 pounds, the Rebel HD maxes out at 3,140 pounds (gas), and the Tremor leads the class at 4,053 pounds (gas).
When it comes to conventional towing, diesel is king and the Duramax-powered Silverado HD ZR2 Bison can yank 18,500 pounds down the road. Power Wagon can only muster 10,620 pounds, Ram Rebel HDs comes in at 16,850 pounds, and the diesel Tremor is rated for 18,200 pounds.
Thankfully it’s not all work, as the HD ZR2 Bison still has the numbers to be competitive on the off-roading spec sheet. Ground clearance checks in at 11.8 inches, and the approach, breakover, and departure angles are 29.8 degrees, 25.7 degrees, and 22.6 degrees, respectively.
Behind The Wheel
Because of how well it drives, it’s sometimes hard to remember that you are piloting an 8,495-pound behemoth. The Multimatic shocks work so well on- and off-road that this big truck rides better than you expect, and really, better than it should. However, the shocks aren’t magic and don’t suspend the laws of physics.
While it can carry pretty respectable speeds on the dirt, unlike the 3,200-pound lighter Colorado ZR2 Bison, it’s not a rowdy whoop killer or dune jumper. Any decent sized undulations will quickly overwhelm the front end and remind you to dial back your Baja ambitions a tad.
Outside of that, the HD ZR2 Bison is a pleasure to drive. From covering endless miles of black top to towing a trailer or finding yourself on a buggy trail in Johnson Valley, this is a workhorse that knows how to have a good time. It’s also a luxurious tool that coddles its occupants in quiet, relaxed comfort.
The biggest issues we noticed were outward visibility on technical trails, especially over that massive hood (thankfully the front camera on this truck is a huge asset off-road), a hill descent system that seems to be working at its limit on truly steep descents, and the old school recirculating ball steering and Hydroboost brakes that are less-than-subtle clues that this is anything but a fully modern truck.
Overview
While the Silverado HD ZR2 Bison isn’t going to be your go-to trail rig, the improvements across the board make it a better all-around truck without taking away from its heavy-duty mission of hauling and towing. The Bison upgrades offer increased capability and improved protection of the truck for those times you might find yourself in unforgiving environs and it truly is a solid and enjoyable do-everything setup, as long as the price of entry makes sense for you.
| ’24 Chevrolet Silverado HD ZR2 Bison CC 4x4 Diesel | |
|---|---|
| Base Price | $91,220 |
| Engine/Trans | 6.6L DOHC turbo diesel V-8/10-speed automatic |
| Horsepower/Torque (lb-ft) | 470/975 |
| Wheelbase (in.) | 159.1 |
| Tire Size | LT305/70R18 |
| Approach/Breakover/Departure Angles (degrees) | 29.8/22.6/25.7 |
| Ground Clearance (in.) | 11.8 |
| Crawl Ratio | 41:1 (est.) |
| Curb Weight (lbs.) | 8,495 |
| Payload (lbs.) | 2,811 |
| Towing (lbs.) | 18,500 |
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This article originally appeared in OVR Issue 07. For more informative articles like this, consider subscribing to OVR Magazine in print or digital versions here. You can also find the print edition of OVR at your local newsstand by using our Magazine Finder.
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