Cooper Discoverer A/T3

Of all the decisions made by the overlander, selecting the proper tire is perhaps one of the most important. But, because tire innovations move at a glacial pace, many overlanders opt to stick with tried and true tires, slow to branch out and try newer offerings. Released in just 2011, you could still call the Cooper Discoverer A/T3 a new tire, and a bit of an unknown to many. We’ve had the opportunity to test this tire over the last year on a variety of platforms and it has handily exceeded our expectations.

The Discoverer A/T3 is a silica-based tire with a five-rib design with the tread elements coupled together to provide optimal on-road handling. The three center ribs are divided to improve off-road traction and the outer lugs are angled for added grip and are said to attribute to the tire’s self-cleaning properties. The zig-zag shape of the siping on each lug helps accomplish a couple things. Primarily, it increases wet weather performance, but it also softens the lugs for improved lug stability and greatly reduces rock retention. To further reduce rock retention, the inner sides of the perimeter lugs feature serrated steps positioned at a slight angle. All this talk of stone retention may seem like much a do about nothing, but I happen to have a long gravel driveway. My BFG all terrain tires would regularly pick up stones by the handful. I shudder to think how many windshield pits I caused.


The first of our vehicles to wear the A/T3 was our 1991 Toyota LJ78. A sizable vehicle fitted with all the mods appropriate for a full-blown overland rig, it sees the typical mix of on and off-road surfaces. Those tires were installed more than a year ago, and have been put through the paces, to say the least. In that year, we have found the on-road manners to be exemplary with no unwanted noise or feedback. Off-road they have performed beyond expectations with the snow performance earning them the highest accolades from Scott Brady who said the A/T3 is the best name-brand all terrain tire he has used in the snow. For a guy with thousands of glacial ice mileage under his belt, that’s a weighty endorsement.


On the other end of the testing spectrum, we wanted to test the Discoverer A/T3 on a smaller, lighter vehicle like our Jeep Patriot project. This being a more road-biased vehicle, it has been a great test of the A/T3’s road manners. On long stretches of pavement at freeway speeds, the tires are quiet, compliant, and feel very much like they are designed for such use. The Patriot’s one glaring shortcoming is a lack of clearance and rigor mortis-like articulation. With one wheel regularly in the air, maximizing the traction control is essential and the A/T3 has been superb in that regard. Because of clearance challenges, lowering air pressure is a last resort, so much of the off-road testing with the Patriot is done at street pressure. On a recent trip to Utah, a freak rainstorm presented un unfortunate opportunity to test the mud-clearing properties of the A/T3. I would say they did admirably considering how nasty Utah’s primordial ooze can be.


At first blush, the A/T3 appears to favor the tarmac, and it does perform well in that setting. However, the snow and off-road performance is a welcome surprise. Whether under a Land Cruiser, JK or Patriot, the A/T3 has more than proven itself up to the task and impressed us at every turn. Pricing is reasonable and the 55,000 mile warranty adds yet one more reason to give them a try.


Christophe Noel is a journalist from Prescott, Arizona. Born into a family of backcountry enthusiasts, Christophe grew up backpacking the mountains and deserts of the American West. An avid cyclist and bikepacker, he also has a passion for motorcycles, travel, food and overlanding.