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Thom Cannell Contributing Writer, GM-Trucks.com December 6, 2018 Last month Chevrolet invited us to test the Chevrolet Bison, a ZR2 derivative with distinctive upgrades that add to its already solid off road capabilities. Built off the already-capable Z7R2, American Expedition Vehicles (AEV) provided the collaborative additions that created Bison. It retains the class-exclusive front and rear locking differentials from ZR2, and high-zoot Multimatic DSSV dampers. The design of the Dynamic Suspensions Spool Valve dampers uses hollow cylindrical sleeves instead of familiar discs. These were used first on race cars including Champ cars, LeMans prototypes and F1 They provide superb off road damping, particularly on rough trails where they offer greater passenger comfort. Getting to the grit of it, a pickup is hard-pressed to have the approach angle of a Jeep, and impossible for a production bed to provide a really short departure. Nonetheless, Bison does a very good job of going over rocks. One of the AEV additions is a set of five hot-stamped Boron-steel skid plates to protect the oil pan, fuel tank, transfer case and front and rear locking differentials, which we tested extensively. “As this is the first Chevrolet vehicle we’ve given the AEV treatment to,” said Dave Harriton, founder and president of AEV, “we wanted to do something special with the industry’s first use of hot-stamped Boron steel.” We think he’s referring to the off-road industry, as hot stamped High Strength Steel is the basis for modern crash-worthy chassis. However, those skid plates kept the rocks out of our oil pan. Some of the Bison upgrades are more cosmetic than necessary, like replacing the bowtie grille a free-flowing CHEVROLET front grille, Bison decals on the bedsides and an AEV Bison logo on the tailgate plus an embroidered AEV on the floor liners and front head rests. Branding, eh? Performance-oriented changes include the stamped steel front and rear bumpers. The front bumper allows adding a winch (would you go off roading without a winch??), fog lamps and integrated recovery points. As a truck designed to venture deep into open spaces, Chevy added 31-inch Goodyear Wrangler Duratrac tires mounted on Bison-specific 12x8-inch aluminum wheels. We tested those, too, and they have plenty of grip on rocks, and in loose dirt. Note that the ZR2 cast-iron control arms and Autotrac transfer case are retained, along with the ZR2’s 3.42:1 axle ratio and front/rear tracks wider by 3.5-inches. Compared to a ZR1, Bison is lifted by two-inches. Our test vehicle was powered by the new 2.8-liter Duramax diesel (186 hp., 369 lb.-ft.) mated to a six-speed transmission. It was the crew cab model; with the short bed which including some AEV upgrades. On our highway drive towards an off-road park, we noted that the Bison was extremely quiet, and not just “quiet, for a truck”. No, it was quiet for any kind of vehicle, including a Cadillac. After switching the transfer case into 4WD-high, we bucked our way towards the promised bigger challenges. Along our trail—nothing extreme but way off the beaten path—we again noted there hadn’t been a single squeak, rattle, or buzz. The only odd sounds in the cabin were from the zippers on our camera bags. Bison’s frame is stiff; there’s no tweaking, everything is absolutely tight. There was no way to call out the suspension and its Multimatic spool-valve-type dampers, however the suspension was supple on the rough trail. Another noise-related note, we picked up no rock noise in the wheel wells despite being pushed around by potholes, rocks and dips. We might as well have been on the freeway, from a noise perspective. Our truck had almost every American Expedition accessory available. There were LED fog or trail-search lights on the hood, a ladder rack and a storage bin system mounted below a false bed. We only lacked the Baja-style intake snorkel. The bolted-on roof rack may have added stiffness to the already ultra-stiff box frame, which allowed the suspension do its work. Watching the vehicles ahead of us, we could see how steady the beds were, and how much the suspension was working. For a stock vehicle, there was plenty of travel available. Bison has a solid rear axle and independent front suspension, and there is a divide among off roaders and rock climbers as to whether a solid axle or independent rear suspension is better. Rock climbers seem to prefer solid rear axles. We thought the ZR2-based Bison chassis with a Duramax diesel made off roading almost a no-challenge event. The diesel engine was totally on-point with torque, needing only a light application of brakes for stability when balancing on rocks. Comparatively, those who had the standard V-6 gasser had a harder time of it, using more throttle to obtain torque, then having to feather the throttle and brake to stay on track. If you've never done rock crawling, you must apply power to get up, apply brake to stop, before being guided down in the correct direction. Yeah, it's really hard to see the front wheels through the engine. One of the options Chevy will offer through dealers is a shorter, cut off exhaust tip. We strongly recommend this if you’re going rock crawling. Many of us “modified” the longer exhaust tips when crawling off rocks. After crawling a rock canyon we grouped to head for lunch. Parked on a hill with loose sand and the tranny set in 4WD high, there wasn't enough traction. Locking the rear differential made climbing the hill as simple as stepping on the throttle, in that low traction situation. Having complete control over axles and each wheel made off roading and rock crawling easy, even for beginners. Note that, in our opinion, the Duramax doesn't deliver optimum fuel economy for the Bison. It's good, but not great. Where it shines is in torque availability for off roading. We can see the Bison with Duramax as a perfect combination for off road camping, adventuring, and modest towing. It's quiet. While on our rock crawls, there was never a sound from the chassis, no wracking, graunching, squeaks or rattles other than when we skidded over rock on those Boron steel protectors. It was billet solid. In fact, we'd go so far as to say our Bison was quieter than a standard Silverado and totally ready for any off road adventure. Interested in the Colorado ZR2? Join the GM-Trucks.com Colorado ZR2 Facebook Group!

John Goreham Contributing Writer, GM-Trucks.com 5-15-2019 The same folks that GM turned to for the specialty equipment on the Colorado ZR2 Bison have created a fantastic tray bed concept of the truck. America Expedition Vehicles (AEV) built the concept for Overland Expo West. The concept truck shows off new high-clearance fender flares that AEV has developed. AEV took the new tray bed concept Bisons on a three-day off-road desert adventure to see how well they new bed would hold up. The post-trip report is that it worked flawlessly. The new fender flares allow for the fitment of 35" wheels without a lift kit. The new tray bed and fender flares are presently in development. AEV hopes to have more information for those interested soon. Follow AEV via its website, or at the company's Facebook page. Images courtesy of AEV and Scott Brady.

John Goreham Contributing Writer, GM-Trucks.com 12-6-2018 These images were recently posted to the Colorado ZR2 club on Facebook by member Matt Feldermann. Matt is an employee at American Expedition Vehicles , GM's partner on the Bison trim of the Colorado ZR2. As you know if you follow the truck, the Bison comes with a bad-ass front bumper. One of the key features of which is to enable a front winch to be mounted. Matt's post helped explain one thing we have always wondered about off-road trucks. Why so few come with a winch option or even a winch mounting point. "Cooling was the #1 concern shared by GM when installing a winch," says Matt. "The positioning of a winch in the AEV Bison bumper is OE validated to have NO effect on cooling whatsoever." Matt also shared that, "You can see a bracket welded to the tube that holds the winch. It’s a bit unorthodox, but that’s what had to happen to fit a winch on while maximizing approach angles." Our thanks to Matt for sharing his images.

John Goreham Contributing Writer, GM-Trucks.com 11-9-2018 Chevrolet announced the prices for its Colorado ZR2 Bison today. The V-6 extended cab Colorado ZR2 Bison starts at $48,045, or $49,645 for crew cab models (including $995 destination). This represents a $5750 premium over the ZR2. Given the additional content which includes rear steel bumpers, full skid plates, and fender flares, plus the Chevrolet-backed warranty, Chevy says this represents a relative bargain. GM offered a comparison to a Jeep Wrangler Rubicon Unlimited. GM says the equivalent Jeep would ring in at $50,025. Dave Harriton, president and founder of American Expedition Vehicles (GM's partner for the Bison), commented on the Bison's pricing, saying, “Although they play different roles, and are for different customers, a fully loaded Rubicon with similar levels of capability and equipment will be over $50,000. However, when looking at other factory off-road vehicles on the market, the ZR2 Bison is unmatched for all-around versatility.”

John Goreham Contributing Writer, GM-Trucks.com 11-9-2018 Chevrolet is building upon its huge sales success of the new generation Colorado with two new special editions. GM credits the Colorado and Canyon with helping the company to become the largest seller of pickups. “The success of Colorado helped reignite the midsize truck segment, which increased 27 percent from 2015 to 2017,” said Sandor Piszar, director of Marketing for Chevrolet Trucks. “It changed what customers expected from a midsize truck, brought new customers to Chevrolet and has inspired competitors to follow Chevy’s lead.” The first Colorado special edition is a street-focused RST is based on the LT trim. The new RST features a monochromatic exterior offset with a black beltline and body side moldings. The RST also adds a black tailgate bowtie, Colorado and RST badges. The RST becomes first Colorado trim to offer 20-inch wheels, finished in low-gloss black. Like the Bison, the RST will wear the flow-through “CHEVROLET” lettered grille. The new Colorado Z71 Trail runner begins with the Z71 package and adds the Colorado ZR2’s underbody protection and rubber. These include aluminum front and mid skid plates, functional rocker protection and Goodyear Duratrac tires. With this new trim, Chevrolet offers four distinct Colorado levels of off-road capability: - Colorado Z71: Z71 Off-Road Suspension, automatic locking rear differential and unique 17-inch painted wheels and all-terrain tires. - New Colorado Z71 Trail Runner: Adds additional off-road protection to the Z71 trim with the Colorado ZR2’s front and mid skid plates, rocker protection and 17-inch Goodyear Duratrac tires standard. - Colorado ZR2: Compared to a standard Colorado, the ZR2 features a factory-installed 3.5-inch wider track and a suspension lifted by 2 inches. Class-exclusive features include front and rear electronic locking differentials and Multimatic DSSV Dampers. The ZR2 also features front and mid skid plates, rocker protection and front and rear bumpers modified for better off-road clearance. - Colorado ZR2 Bison: The ZR2 Bison adds even more extreme off-road capability with five hot-stamped Boron steel skid plates and stamped steel front and rear bumpers with front winch provisions and rear recovery points.

John Goreham Contributing Writer, GM-Trucks.com 10-16-2018 Matt Felderman of American Expedition Vehicles posted an upskirt shot of the new Bison today (at the Facebook Colorado Owner's Club) that illustrates the full skidplate treatment the vehicle receives as standard equipment. Matt says, "Everything you see is stock, with the exception of the trans skid which we will be offering separately." Coupled with the rock sliders every ZR2 has, the Bison now seems pretty well protected from off-road abuse. For more details on the Bison, check out our full overview.