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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!

Zane Merva Executive Editor / Publisher - GM-Trucks.com October 10th, 2019 Chevrolet is giving the not so subtle hint that the rumored Silverado ZRX model is about to become reality. Today, the brand announced that a "Silverado Race Truck" would compete in this weekend's Laughlin Desert Classic alongside the Hall Racing Colorado ZR2. Interestingly, the Silverado will compete in the Desert's 1200 Stock Class, which limits changes to suspension, under body, and race-safety equipment. What does that mean? This truck is not only ready to race, it's close to production too. The "Silverado Race Truck" is outfitted with a number of aftermarket goodies that look like they were ripped right off a Colorado ZR2. Starting as an LT Trail Boss with the 6.2L V8, the Silverado Race Truck is outfitted with a long travel suspension, front and rear jounce shocks and Multimatic DSSV dampers. In short... the modifications that Chevy applies to the Colorado for the ZR2 model. Why didn't Chevy just come out and call this the ZRX Race Truck? We're not sure, but there's no doubt this is a low flying announcement made to pave the way towards an eventual Silverado model that emulates the ZR2's success in a larger package. Whether that's enough to take on the Ford Raptor is too early to determine. Stay tuned for updates on the "Silverado Race Truck" and future Silverado ZRX.

Zane Merva Executive Editor / Publisher - GM-Trucks.com October 8th, 2019 Chevrolet is ready to race the 2021 Colorado. Like, really ready to race. This week in fact. The new face for the Colorado mid-size truck will make its public debut October 10th during the 2019 Method Race Wheels Laughlin Desert Classic and will be driven by Hall Racing. Here's a sneak peek at the all new face of the Colorado. Chevrolet also gave us a showing of the production 2021 ZR2 that will debut in one month at the 2019 SEMA Show in Las Vegas. Check back with us in November for our first hand take at the new ZR2 when we visit the SEMA Show. Anyways, let's take a look at the changes. What's new with the 2021 Colorado? First off, the changes so far seem to be cosmetic and packaging only. No new features or changes in specs have been announced yet. However, the exterior has been warmed over to bring it in line with the Silverado's front end, without breaking the bank on a full redesign (which is expected in the 2023-2024 MY time frame). Here's the announced 2021 changes. New front end appearance for ZR2 model. Only Colorado model to have "Flow-through Chevrolet Fascia". WT, LT, and Z71 trim levels will receive updated center bars, lower fascias, and new front skid plates. WT and LT will feature "all-new" gold Chevy bowties while the Z71 trim is adorned with a black bowtie. All models receive embossed 'Chevrolet" tailgates and ditch the traditional bowtie on the rear of the vehicle. A new "Sand Dune Metallic" will be offered on Z71 and ZR2 models only. What do you think about the new face of the Colorado?

John GorehamContributing Writer, GM-Trucks.com11-8-2018 General Motors made an unusual request today of GM-Trucks.com. Our contact at the Chevy Truck department asked us to report that GM is launching a new campaign to adjust the sensitivity of the airbags in the Chevy Colorado ZR2. This is a refreshing change from the industry standard practice of soft-pedaling recalls and product programs. Here is the unedited information we were asked to convey: As you are aware, there have been reports of Colorado ZR2 owners whose roof-mounted side airbags deployed while off-roading. Upon learning of this issue, Chevrolet took immediate action to understand the root cause and create a solution. Today, we notified Chevrolet dealers of a customer-satisfaction initiative to recalibrate the thresholds for the roof-mounted side airbags for ZR2 owners. The updated calibration is available as of today, and will be installed free of charge the next time the customers takes their ZR2 to a Chevrolet dealer. There have been 11 reports of Colorado ZR2 owners whose roof-mounted side airbags deployed while off-roading. Chevrolet is working to reimburse those ZR2 customers for the cost of repair, provided the event data was available to confirm the incident. We are incredibly proud of the ZR2 and the off-road capability it offers, and are encouraged to see customers are using the truck as intended. If customers have questions, they should contact their local dealer or Chevrolet Customer Assistance at 800-833-2438 GM-Trucks.com readers may recall that in May we covered the news that owners were beginning to report that the airbags in their Colorado trucks were deploying while off-roading (and not in a crash). You can read the prior full report here and see more images. Our reporting leaned heavily on images and reports from GM-Truck.com member Joe F. Since Joe's information was made available, other owners have also reported the same problem. We will do our best to get new information from Joe F. and how he is reimbursed. Our thanks to GM for asking us to be involved in disseminating this important product update program.

Zane Merva Executive Editor, GM-Trucks.com 5/7/18 Our trusty Spy Photographer has just caught the all new ZR2 Bison undergoing testing. We first talked about the Bison in early April when GM first registered a trademark. Here's what our photographer has to say followed up by the photos they captured.

Zane Merva Executive Editor, GM-Trucks.com 5/15/2017 Last week we spent two days driving the all new 2017 Colorado ZR2. It was awesome and we'll have our first drive review coming up soon. In the meantime, it's important to understand what makes the ZR2 more than just a lifted Colorado with big tires. Dynamic Suspensions Spool Valve, or DSSV for short, is a super high-tech shock technology found in motorsports and other really expensive supercars. It's also the heart of the new ZR2 and the first time this shock system has ever been used on a truck. It's also only the second time the technology has been used in a production Chevrolet (the first was the Camaro Z28). So sit back, relax, and take 8 minutes to learn more about the single most important item on the Colorado ZR2 that makes it far more than just a lifted Colorado with big tires.

John Goreham Contributing Writer, GM-Trucks.com 2-10-2017 Hagerty, the folks that insure classic vehicles and maintains the largest classic car network in the world, says that three Chevy vehicles make the list of its picks of 2017 models that could become classic cars. The Camaro ZL1, Corvette Grand Sport, and GM-Trucks.com favorite, the Colorado ZR2 were all singled out by Hagerty as possible future collectible classics. Hagerty says that, "The 2017 Camaro ZL1 has a stat sheet that would make last year's Corvette nervous, and comes to the table ready to race. The legend continues to inspire today just as it did 50 years ago, as the Camaro reaches a whole new audience with this instant collector's item." Commenting on the ZR2, Hagerty says, "The ZR2 comes with a suite of off-road tech including dynamic shocks, locking front/rear differentials, increased ride height and widened track. Its future collectability lives in the hands of Chevrolet's production volume planning staff." Of the Corvette Grand Sport, the group said, "...the Grand Sport has the technology to compete with the big boys while offering a striking visual reference to its ancestors: the 1963 and 1996 Grand Sports." So which of the three do you think will be the bigger future collectible?