2024 Chevrolet Silverado HD ZR2 Bison Review: The Cost (And Compromise) Of A Tow Star

After the popularity of the mid-size Colorado pickup's off-roading ZR2 package, Chevy launched the first heavy-duty 2500-class ZR2 last year on a drive program in and around Johnson Valley. Running a massive pickup through the same stretches of desert as the King of the Hammers race course proved that even something as big as a Silverado 2500 can handle a significant level of off-roady truck stuff, while the beefier drivetrains also make on-road towing and hauling a serious consideration for potential customers, as well.

But the wide-open highways of Johnson Valley and Palm Springs afford such a big truck plenty of space, so the question remained how well a pickup of this size fares in town. Almost a year later, I borrowed a fully loaded Silverado HD ZR2 Bison equipped with the Duramax diesel engine to use as a daily driver on some of the most treacherous terrain of all: the mean streets of West Los Angeles.

The first thing to note about Chevy's (and GMC's) heavy-duty lineup helps to set the trucks apart from Ram and Ford. Unlike the competition, the Silverado (and Sierra) uses independent front suspension with torsion bars, rather than the more typical solid front axle with coil springs. Doing so theoretically improves on-road driving dynamics and steering feel but also—and I'll harp more on this later—weighs far less than the front end of a truck equipped with a fully solid front axle.

Then, of course, the "base" ZR2 and Bison both get Multimatic DSSV shock dampers, as well as a locking rear differential on the HD pickups—though not a front locker as on the 1500-class ZR2 and Bison. The use of Multimatics further sets GM apart from Ram and Ford, as these passive dampers provide spectacular performance, both on-road and off, especially on the smaller Colorado ZR2 that inspired the addition of an HD version to the lineup.

Unlike the 1500 ZR2 and Bison, though, the 2500 does hit the market equipped with Goodyear 35-inch mud-terrain tires. The fact that the smaller Silverado doesn't, Chevy engineers told me at Johnson Valley, comes down to the fact that the older platform simply wasn't engineered to handle that much tire diameter or width. Keep an eye on the next generation of 1500 Silverado, since 35s now seem de rigueur amid the escalating off-road pickup truck wars raging between Ford, Ram, and Chevrolet (and, to an extent, Toyota).

The rest of the Silverado arrived outside my apartment as something of a known quantity. The 6.6-liter turbodiesel V8 pumps out an ungodly amount of torque, at 975 lb-ft, and up to 470 horsepower—big gains versus the base gasoline V8 at 401 horsepower and 464 lb-ft of torque. An uprated Allison 10-speed automatic helps to handle that additional output.

The 2500's interior also largely matches the 1500 class, though with a column gearshift lever and some four-wheel-drive controls moved to the left of the steering wheel. The rest of the utilitarian dash, topped by a large touchscreen and configurable gauge cluster, manages to split the difference between functional and luxurious, without the more premium touches of a GMC Sierra. Ventilated seats come standard, a must while off-roading in the hot SoCal desert, though not the massaging seats of the GMC.

The top-spec Bison package, another recipe borrowed from the Colorado and Silverado 1500, largely adds cosmetic and protective parts built by American Expedition Vehicles: a set of 18-inch wheel shod in the Goodyears, substantial steel bumpers and stamped steel skid plates, and AEV-branded floor mats. This specific truck also features the optional electronically extending and retracting running boards, which might look similar to rock sliders but, as we learned quickly in Johnson Valley, most certainly are not.

The Duramax diesel, Allison transmission, and AEV Bison package all contribute to an unbelievable curb weight of 8,495 pounds. And the side steps make life with the HD Bison much easier, because this thing is B.I.G. (in all caps, bolded, italicized, and underlined). The square hood, wide track, full-size crew cab, and bed create a physical footprint that seemingly requires a lot of thought to drive in town.

And yet, on my block that confusingly combines head-in and parallel parking, after a couple of days dailying the HD Bison, I started fitting the truck into smaller and smaller spots. Sometimes I needed to K-turn in order to make sure I parked nice and straight without crossing the head-in lines. Here, the easier steering of independent front suspension helped to mask the front-end's size and weight, I'd guess. Plus, thanks to the Bison protection package, I felt confident pushing the front tires right up to the curb because I never needed to worry about tree roots damaging the truck. While parallel parking, the touchscreen with high-definition camera, as well as the large side mirrors, also helped mightily.

In short, I acclimated to the size of the HD Bison in town quite quickly, even if this is just about the biggest truck possible short of a 3500-class with duallies. And the sheer size also makes the interior quite comfortable, with plenty of storage volume and elbow space to go along with more than enough head and legroom for both the front and rear seats. Even the wireless Apple CarPlay popped up quickly once I set up the initial Bluetooth connection.

Meanwhile, the drivetrain simply delivers torque for days. I had hoped to do some towing with the HD Bison but unfortunately, the plan evaporated at the last minute. The prospect of hauling a sports car in a 5,000-pound, 20-foot trailer seems unlikely to stress such a beefy diesel engine, though the lack of GM Super Cruise due to the ZR2 and Bison packages' off-roading bumpers makes for something of a bummer.

Without towing, though, that Duramax V8 never feels underpowered, whether accelerating away from stoplights or passing at highway speeds while blasting up steep grades. The diesel grumble also helps to cover up most of any potential tire hum from the 12-inch-wide Goodyear Wrangler Territory mud-terrains and their big, blocky treads. (Goodyear's tires have come a long way in the last few years in this regard, to be fair.) The upright profile can create some wind noise, though, especially when battling a headwind or crosswind.

And then, of course, we come to the subject of fuel economy due to the HD Bison's size, weight, and aerodynamics. Here the Allison 10-speed no doubt helps, with generous gearing to find the perfect RPM for every scenario. Final-drive ratios, front and rear, of 3.42 probably help with fuel economy, though the onboard computer still showed just over 14 mpg from mostly city driving around LA, plus one trip out to Willow Springs. I never needed to fill up the 36-gallon fuel tank—whew—so I can't 100% confirm the truck's economy stats, but even assuming slightly less optimistic numbers, the HD Bison performs fairly well for something so large. I'd guess that somewhere in between 18 and the EPA's 20 mpg estimate for highway cruising without towing sounds fairly realistic.

Rather than towing, I did help a friend move out of his house, which put the truck bed and Multi-Flex tailgate to good use. As always, I started wishing for an eight-foot bed and smaller backseat but apparently, American buyers overwhelmingly disagree with me when it comes to the higher-spec off-roading packages. Oh well, I still packed the bed with some gimmes—shelving units for storing moto gear in my garage mostly—plus some lumber cut to seven-feet long that he wanted to get rid of after years in the same location.

The trip out to Willow Springs for a motorcycle track day also showed how the nifty Multi-Flex tailgate design can be put to good use. I rested my gloves and helmet on the smaller shelf without needing to fold down the full tailgate, and still had plenty of space for snacks and water, too. On a hot day, I left most of my gear in the spacious backseat with the windows cracked, then remotely started the truck from afar with the key fob to blast the A/C before driving back home.

Headed out to Willow Springs on the 405, though, the HD Bison's weight showed up on choppy surfaces, as the whole truck bounced up and down restlessly for minutes in a row, Multimatics struggling to contain something so huge and heavy. My mind revisited the off-roading trip, where the rear leaf springs and front torsion bars handled washboards with significantly less compliance than the 1500-class Bison (not to mention the sublime performance of the Colorado ZR2 and Bison, the latter of which adds Multimatic bump stops, too). 

Perhaps Chevy sprung the truck too tightly, in the hopes of keeping body roll to an absolute minimum—though I'd happily trade some compliance in exchange for absolutely flat handling. At least high-speed driving again reveals the advantages of independent front suspension, more closely approximating the steering dynamics of a car or truck with normal proportions rather than something so monstrously enormous.

Then there's the pricing. The Heavy Duty Silverado 2500 starts at $69,600 for 2024, which doesn't sound too bad. Check the boxes for the turbodiesel and ZR2 and Bison, though, and all of a sudden that starting sticker balloons up to a whopping $95,680 as tested. Woof, adding on almost another half sure makes the 1500-class Silverado Bison with the standard Duramax straight-six start to look pretty good. In fact, a friend of mine bought a Silverado 1500 ZR2 on my recommendation, after starting out thinking he needed the 2500 to tow his racecar.

The smaller truck with the smaller Duramax nails a sweet spot, capable of towing a respectable 9,000 pounds with a much lighter 3.0-liter engine that helps to keep weight down closer to 6,000 pounds—and in the process only makes on-road and off-road driving much easier for the Multimatic application, as well. Still, for the real hardcore truck stuff, the 2500 HD makes a strong case as the way to go. And given the sheer limitations of physics, living with the biggest Bison never ended up causing me any problems, even on the cramped streets of West LA.