AEV Chevrolet Colorado ZR2 Bison review

American Expedition Vehicles (AEV) is best known for its work with Jeep and Ram vehicles from the FCA stable.

For more than 20 years the skilled team at AEV has been turning these 4x4 vehicles into off-road weapons, but unlike trucks from many custom shops and modifiers the AEV rigs are built with an OEM attention to detail, product integration and quality. This comes after years of working closely with Jeep on other vehicles including show specials.

27

In more recent times, the AEV badge has been seen on the Chevrolet Colorado ZR2 midsize pick-up. The ZR2 is the high-performance version of the US-Colorado and it comes with off-road-focused suspension and a bolder look. As is its way, AEV has taken the ZR2 to the next level with a factory-backed collaboration to create the ZR2 Bison.

The AEV ZR2 Bison debuted at the SEMA Show in 2018 and went on sale at Chevy dealers in the USA throughout 2019. Also at SEMA that year was a ZR2 Bison concept that featured a swag of off-road extras to really make the product stand out.

In the year since then, AEV’s founder and president Dave Harriton and the team have developed those Bison extras to make them available as options on the vehicle, and for SEMA 2019 they displayed this stunning example bearing the full kit, now called the AEV350.

What makes the ZR2 Colorado more than just another styling exercise is its DSSV Multimatic suspension. These clever shocks come from the Chevrolet Performance team and give the truck a best-of-both-worlds suspension tune that delivers firm and stable on-road dynamics while it eats up bumps and ruts in the rough stuff. It might sound too good to be true, but we’ve driven a stock ZR2 and the shocks work unbelievably well.

27

What wasn’t too good on the standard ZR2 was the relatively small tyre and wheel package fitted by Chevy, with the 31-inch all-terrain rubber getting lost under the lifted wheel arches and struggling when the going got tough. Even the ZR2 Bison only rides on 31s, albeit on AEV wheels, but the deal gets real with the AEV350 hop-up kit that squeezes 35s beneath the bespoke flares.

Significantly, the new, American-made AEV Highmark wheel-arch flares allow those 35-inch BFGs to fit under there without any suspension lift over and above the ZR2’s factory 50mm lift (over a stock Colorado).

The front-end is assisted by a GM Performance levelling kit with high-angle ball joints and a GMP tie rod reinforcement kit, to maintain suspension geometry and strength with the bigger tyres fitted. The extra ground clearance offered by the 35s transforms the Colorado to give it the off-road capability it deserves; crawling over rocks, cresting dunes and negotiating ruts with ease.

27

Should the Colorado run out of ground clearance, the underbody of the Bison is protected by AEV’s exclusive hot-stamped boron steel (HSBS) skid plates. HSBS is stronger than regular steel and the plates are available to protect under the engine, transmission, transfer case, fuel tank and rear differential. The Bison’s off-road performance is bolstered by the ZR2’s factory differential locks both front and rear ... to think we can’t even get a factory diff lock in the rear of a Holden Colorado!

To compensate for the larger rolling diameter of the 35-inch wheels, the final-drive ratio in the diffs has been shortened to 4.11:1. This Bison is powered by the Duramax 2.8-litre diesel engine we are familiar with in Australia, and it gets the Americans excited because it’s the only diesel engine offered in this class of truck there. The sound, feel and the performance of the engine is all very familiar to us, and none of those 500Nm are lost to the bigger tyres.

27

One of the things we love about driving AEV trucks is that, not only do they perform well off road, they drive just like an OE-stock vehicle on the highway. Most AEV vehicles run Bilstein shocks, so they ride better than stock.

The AEV350 retains the DSSV dampers and features none of the pitching and wallowing that many lifted vehicles exhibit, and there are no unusual noises coming from underneath; just comfortable highway cruising, with the BFGs humming beneath. This comes from AEV’s philosophy of using the minimum lift possible and keeping the suspension geometry as close to OE as possible. Even on some of the company’s bigger Jeep and Ram rigs that roll on 37- and 40-inch tyres, the trucks still ride and steer as good as factory ... and in most cases, better.

27

The wheels on the SEMA ’19 Bison are AEV’s Crestone DualSport alloys that can be used with or without a beadlock. They are US-DOT approved, but using beadlocks on the street is legal in some US states and not others – and not at all here in Australia. The beadlocks are best saved for off-road use, and a feature of the Crestone wheels is that AEV offers a protection ring that can be fitted in place of the beadlock ring to protect the rim from kerb or rock scrapes.

The one issue with fitting 35s to the Colorado is finding a spot to mount the spare; the bed mount in this vehicle was a prototype, and the production version that will soon be available looks a bit different.
Other trick AEV gear on this truck includes the AEV low-tube Bison bumper with Baja Designs light bar and driving lights; AEV winch mount and winch; AEV intake snorkel; AEV Bison rear bar; AEV interior trim and switch panel for light switches; and that uber-cool colour which Dave calls AEV ZC Green. All the AEV vehicles at the SEMA Show were painted in this custom colour.

27

The AEV350 package on the ZR2 certainly makes a good thing better, giving the Colorado much-needed ground clearance and the rubber you want for rugged off-road use. All the parts work together, fit better than OE and are well integrated into a total package.

The only real problem with the AEV kit is that little if any of it will fit on your Holden Colorado. That’s right, the US-built Chevrolet Colorado is a different car to our Thai-built Holden and it rides on a different platform altogether, so AEV is just teasing us Aussies with all this good gear. We can only hope the next-gen Colorado will be built on a new global GM platform, as has been rumoured, and parts will be interchangeable on both sides of the Pacific.

Gladiator good gear

27

When we went out to play in the desert with the AEV Colorado, the team had all its SEMA Show vehicles with them including the RAM 2500 Prospector, JL Wrangler and the new Gladiator; all of them resplendent in custom ZC Green.

The good news for Australians is that most of the AEV kit for the Jeeps and Ram will fit our vehicles and is available through AEV dealers here. Of particular interest was the AEV-equipped Gladiator fitted with AEV front and rear bumpers, AEV Wheels, suspension and snorkel; and most of this kit is ready to go.

If you’re looking for some of the best gear available to outfit your new JT Gladiator, then the AEV products are worth a look.