More Bite than Bark

The phrase, “jack of all trades, master of none” needs very little interpretation. I think of a middle-aged man in worn out work boots, holey jeans, and a cheap stained t-shirt with a pack of Marlboro Reds protruding slightly from his pocket. A beat up old tool bag with well used, but sharp and precise, tools in his grip—he’s a man that can get it done.

You remember what a bargain his labor prices are, as you turn the other cheek to his short comments and surly disposition. Finding a solution quickly and getting straight to work, you try to force from your mind that he didn’t pull a permit like the expensive Journeyman you spoke to would have. Much like this man, the Cooper Discoverer ST Maxx is a rugged-looking specimen with sharp tools at its disposal. Overland travelers like myself, tend to demand a great many things from a set of tires. Often driving thousands of miles at interstate speeds with a literal ton of gear and vehicle armor to get to our backcountry spot of choice, where we air them down and explore hundreds of miles of rocky, root strewn and muddy tracks that would give the minivan crowd a stroke. If that doesn’t sound like a tall order already, these same vehicles are often used as daily drivers to dodge morons on the way to the store, getting to and from work in the snow and ice, and even over nails and screws on the job site. Did I mention we also want them to be relatively light, to keep down rotational weight? I think you’re starting to get the picture.

Rated as a M+S (mud and snow) tire, I tend to think of the ST Maxx as an aggressive all-terrain. The voids between the lugs are larger than most ATs, but smaller than most MTs, which contributes to its off-highway performance, while retaining good, “keep your elbows off the dinner table” manners on the asphalt. While there are a few sizes available in lighter C and D load ratings, this commercial grade traction tire is most readily available in load range E for 16 to 20-inch modern wheel sizes. My 4Runner is heavier than most mid-sized SUVs due to its added steel protection on all four sides and other expedition gear, but I was still a little concerned about running such a heavy weight rated tire, as having sidewall flexibility off road was also a priority. However, the first time I aired them down to 18 psi (actually a very high starting point for off-highway driving), I was pleasantly surprised. Air them down to 10-12 psi, and they will defy gravity.

Cooper’s proprietary cut and chip-resistant tread compound, combined with their patented 3 ply Armor-Tek3 construction, make for one tough tire. A friend of ours took a 2-inch chunk out of the sidewall on a sharp rock and the tire didn’t blow out—or lose any air at all. In the end, he replaced it about a month later just for peace of mind, but it not only got him home without mounting the spare, but was perfectly fine till safety at interstate speeds became a concern. Years ago, I had a similar chunk taken out of another big name brand tire that ended up with me winching out of a boulder field to a safe spot to mount the spare. Apples and oranges? Not the same rock or trail, so maybe. But one scenario ended with an abrupt Pssshhh!!, and the other wasn’t discovered till later. I’ll let you be the judge on that one.

Any time you intend to put a larger, more aggressive than stock tire on a vehicle, it’s a good idea to chalk test them especially with a heavier load rating. Typically, the recommended air pressure written on the door sticker will be too high, and your new tires will start to wear unevenly. I chalk tested mine, after finding some slightly uneven wear after 1500 miles. As it turned out, I was running 7 psi more than I needed, and now 5000 miles later, the ST Maxx’s are wearing perfectly flat and slow. It may be years before I can tell you how many miles I got out of my current set, but I can tell it will be on par with, but likely better than most I have tested in this category. I’ve been told of several sets still going strong in the upper 50k range, with regular rotation and good alignment.At highway speeds, or 5-10 over the speed limit (as tested) the ST Maxx feels solid, corners well in wet and dry asphalt conditions with relatively low noise. Of course, they’re not as quiet as a street tire, just look at them. But for someone who’s been running mud terrains for years, they are very quiet in comparison. I have heard of some traction irregularities on gravel roads, one of which may or may not have contributed to my friend’s Tacoma landing on its roof. I don’t know the exact circumstances of this incident, and I wouldn’t even mention it if it wasn’t for having noticed it a little myself. I can’t quite put my finger on it, but they don’t inspire quite the same confidence as other tires I’ve used on dry washboard roads. That being said, if you drive like a normal person you’ll probably call me crazy. I only barely noticed after switching from one of the stickiest mud terrain tread patterns ever made (the MTR), so don’t let it scare you. It’s very, very minimal.

As mentioned above, when aired down the traction on granite, sandstone, dirt and uneven terrain has been outstanding. They fall predictably in between a dedicated mud terrain, and an all-terrain in sloppy conditions like mud and snow. What I mean by that is that they don’t self-clean or dig in quite as well as a true mud tire, but the decent size voids between the lugs do better than most all terrains. Snow performance is really good, though a decent all-terrain tire with more siping is going to be better on ice, though the ST Maxx is far better on ice than most mud terrains I’ve used. Most. 

If it sounds like an in-between, middle of the road tire, that’s because it is. But don’t let that fool you. The Cooper Discoverer ST Maxx doesn’t come out on top in any one performance category, nor does it fall short in any of them. There isn’t one thing it does poorly. It is barring none, the most versatile tire I have used to date. As far as weight and prices are concerned, they obviously vary with size, but I think you’ll find them somewhere right down the middle as well—shocking, I know. I have been asked countless times if I would buy them again, and the answer is always yes. Turns out, this jack-of-all-trades cleans up pretty good at the end of a long hard day.