Abraham Maslow is credited with saying, “I suppose it is tempting, if the only tool you have is a hammer, to treat everything as if it were a nail.” In our case, every road looks like a trail. We often end up buying mud-terrain tires as a result. There is no denying that aggressive tires look cool, but they require certain compromises as well. Mud-terrains tend to be louder and more difficult to balance than all- terrains and typically do not last as long. These are not the attributes we wanted on our 2008 Ford Super Duty tow rig, so we started to look for a tool other than a hammer.
If we are honest with ourselves, the best choice for a tow rig is a stock-sized highway tire in Load Range E. Not only would that be boring, but it would also limit where we could drag our trailer and would prevent us from using the Super Duty for hunting and backcountry exploring. The compromise was to put a 35-inch-tall Cooper Discoverer A/T3 tire on the Super Duty instead of the larger and more aggressive 37-inch Discoverer STT Pro tires that we were drooling over. We will save those for our wheeling rig.
In this particular case, compromise is not a dirty word. The Cooper Discoverer A/T3 are perfectly suited to our 4WD tow rig, which sees daily driving, lots of miles with a trailer behind it, and occasional off-road use on hunting trips. The Discoverer A/T3 has a silica-based tread compound that has proven to be incredibly chip resistant off-road. It provides excellent wet-weather traction. The generous siping on the tread blocks also contributes to how surefooted the Coopers are on wet and icy roads. If you have ever had to pull a trailer over a mountain pass in the winter, you can certainly appreciate these qualities.
After putting over 10,000 miles on the Cooper Discoverer A/T3s, we are very proud of ourselves for being grownups and choosing a moderately sized all-terrain tire for this application instead of the mud-terrain tires that we are normally drawn to. We have added a tool other than a hammer to our toolbox, and the A/T3s come with a 55,000-mile tread wear warranty so we have plenty of miles left to appreciate our decision. Maybe we should try and compromise more often.
The Discoverer A/T3 tire uses a five-rib design that helps evacuate water and resist hydroplaning. The generous siping inspires confidence in snow and ice, making this tire a great choice for any season.
While the Cooper Discoverer STT Pro would be a better choice for deep mud, the A/T3 does an admirable job of self-cleaning with some wheel speed. The 17/32-inch tread depth certainly helps in this regard.
One area we feel could be improved on the A/T3 is the two-ply sidewalls. While we never experienced any punctures, for peace of mind we would prefer to see Cooper’s Armor-Tek3 sidewall construction as found on the company’s S/T Maxx and STT tires.
The Cooper Discoverer A/T3 tires are whisper quiet on the street. While we spend as much time in the dirt as possible, this is a truck that primarily sees street use for daily driving and towing.
We mounted the Cooper tires on Method MR309 Grid wheels. The wheels measure 17x8.5 with zero offset to reduce steering effort and scrub. They are available in matte black or titanium; we chose the latter.
The tires felt stable and confident at speed both on -road and off. After logging hundreds of miles off-road, including spinning the tires to get up some loose hills, we were impressed by the lack of cutting and chipping in the tread.
The all-terrain tread pattern of the Discoverer A/T3 means that they are far less prone to digging than a more aggressive mud-terrain tire. As a result, they perform quite well in loose dirt and sand, keeping our heavy Super Duty from sinking.
The Coopers we tested were 35 inches tall, but the Discoverer A/T3 is available in sizes ranging from 30 to 35 inches tall for rim sizes from 15 to 20 inches. For 17-inch wheels, 37-inch tall tires are also available.
The voids on the Discoverer A/T3 are not as wide as those on some competing all-terrain tires, but they are just as deep. One benefit of this that we noted was that the A/T3 tires are not as prone to picking up small rocks and tossing them into the fenders as other all-terrains are.
SpecificationsCooper Discoverer A/T3
Size Tested: LT315/70R17
Load Range: D
Maximum Load (lb @ psi): 3,195 @ 65
Sidewall Construction: 2-ply radial
Approved Rim Width (in): 8-11
Tread Depth (in): 17/32
Tread Width (in): 10
Section Width (in): 12.6
Overall Diameter (in): 34.3
Weight (lb): 63
Sizes Available: 57 sizes from 30 to 37 inches for rims 15 to 20 inches in diameter