The Cooper ST Maxx Tire is a part of Cooper’s elite Discoverer line. First released in 2011, this tire was designed for both on- and off-road handling and comfort. It was developed for trucks, large vans, and SUVs. The tire has now been out for several years. Has it delivered on its promise? Let’s check out this tire, and hear from a team that put it to the test.
About the Cooper ST Maxx Tire
Cooper Tire and Rubber Company is regarded as a leading competitor in the tire industry. Its Discoverer line has been in production for about 30 years. It has manufacturing facilities on three continents, and has produced millions of tires which have been distributed around the world.
The Cooper Discoverer ST Maxx Tire’s 3-ply Armor-Tek3 construction adds strength to the sidewall and tread area. There are two polyester plies that run across the tread from bead to bead. The third ply runs at a 45-degree angle from bead to bead. The tire also includes an added angled ply construction that absorbs and dissipates tire impact forces incurred during off-road conditions.
Added to this proven-to-be-reliable construction is a new compound, designed to be cut- and chip-resistant. It is formulated with a blend of natural rubber and silica. It provides wet traction and improved handling on highways, rocks, gravel, and unpaved terrains. Combined with the construction, it provides protection from punctures, cuts, and chips, and provides commercial-grade traction on rough terrain.
In the hybrid 4-5 rib tread design, in which center blocks alternate between a four-rib and five-rib pattern, ribs are placed strategically within the lateral grooves of the tread design to help discharge stones. They quickly eject stones, rocks, mud buildup, and other debris. The tread design consists of one nylon, two steel, and three polyester plies.
The tread block pattern offers increased water evacuation from under the tread, enabling better wet traction, and the buttress area has been optimized to provide additional off-road traction, along with puncture resistance. The tire also features additional micro-gauge sipes to enhance traction on both wet and soft surfaces.
The tire also offers noise reduction. Though it is designed to be tough in any condition, many reviewers have expressed surprise at how quiet it is. And although it is an excellent off-road tire, it is also acceptable for everyday driving on streets and highways.
For those who use their vehicle to carry heavy-duty loads, this tire carries an E load rating. It also comes with studdable lugs, for increased wintertime performance.
Due to its resistance to punctures and ability to evacuate water and debris, the Discoverer ST Maxx also experiences a prolonged tread life. Cooper includes a standard limited warranty as well.
Performance Test Results
According to a review by the Tire Review Team and several others of the Cooper ST Maxx, it performed exceptionally well in testing. The 3-ply tread design provides superior protection and durability. The tire’s dry traction is outstanding on any surface, whether paved, dirt, or gravel. It has impressive grip and stability.
While most AT or MT tires find wet road surfaces to be a challenge, the Cooper ST Maxx had no problems, with better than average wet road traction. Driving in wet road conditions will be much safer and easier, offering peace of mind in bad weather.
The ST Maxx tire is a monster in off-road settings of virtually all kinds. The tire was tested on dirt, gravel, rock, grass, and creek beds, and it excelled each time. It also drove through mud very well, and evacuated the mud adequately. However, heavy, thick mud presents a challenge. But it performed well for moderate amounts of mud.
The Cooper ST Maxx is a heavier tire than your standard MT tire, weighing in at 60 pounds. The effect of this weight on steering response can create a noticeable resistance that can be felt when driving on city roads and highways. While it is noticeable, it is not enough to become an issue. It creates a feeling of power and added control according to testers.
When tested in winter conditions, the tire drives through snow with ease, regardless of snow depth. It performs just as well on ice and slush. The same features that help evacuate stones, water, and mud also help minimize snow, slush, and ice chips. And as mentioned earlier, Cooper has included studdable lugs, for those who encounter severe winter weather conditions.
Regarding ride comfort and noise level, the tire was tough in all conditions, with an actually pleasant ride. The tire is quiet on the highway with a comfortable, relatively smooth ride, even with an ‘E’ load range rating; although the ride may still be slightly stiffer than with most load range C or D tires. The tire may be a little noisier than some all-terrain tires, but quieter than some mud-terrain tires.
Tread wear is definitely above average. The tread compound holds up to off-road conditions, and increases mileage. Though there is no mileage warranty offered by Cooper, these tires should be good for over 60,000 miles before seeing the wear bars.
The ST Maxx has good steering response, ride comfort, and tread wear, and ratings of “excellent” for tread toughness, dry traction, wet traction, off-road traction, and winter traction. Overall, the Cooper ST Maxx Tire delivers solid performance. It’s recommend for trucks and SUVs that spend a lot of time off-road, or that do a lot of towing or hauling. It’s also recommend for construction trucks and vehicles that drive off-pavement and haul heavy loads.