I’ve run a lot of tires on a lot of different rigs. I worked for both Discount Tire and Big O a few moons ago. I’ve managed to never lose a bead along the way, and my only sidewall puncture was in a parking lot when I buried a piece of a Chevy Malibu’s taillight in my right rear Bridgestone Dueler. But we don’t need to talk about that right now. The point is that I’d like to think I’ve gathered enough experience with tires over the years to provide my first impressions of the Cooper STT Pros.
I haven’t ran tires this aggressive in years; ever since I was running 33x12.50-15 BFG KMs on my Jeep ZJ. And while the STT Pro’s aggressive tread design is obvious, its designation is open to some interpretation. It’s not a strict “mud terrain” tire, in the vein of the KM or Goodyear’s MTR. In fact, Cooper offers a tire called the MTP that is meant to serve that segment. The Pro is closer in competition with Goodyear’s Duratrac and BFG’s KO2 than it is the pure trail tire class. And Cooper even offers another all terrain option (ST Maxx) that is a bit less aggressive, while still being well ahead of say a BFG Rugged Trail or Goodyear Wrangler Trail Runner, in my opinion. In short, I find the STT Pro to be a more trail-oriented alternative to the Goodyear Duratrac - a tire I have run four times in three different sizes, and one which I still find to be my benchmark, despite some shortcomings. These are the tires I had on the FJ before installing the Pros, and there are some similarities in tread design, as well.
What exactly brought me to the STT Pros, you ask? Well, I ran the Cooper Discoverer ATPs in the 285/70-17 size on my Tacoma for the better part of a year, and was blown away with them. I was able to do some actual rock-crawling (in an IFS truck, no less) with the tires at their full 35 PSI last year during some informal testing. This inspired some confidence in the brand, along with the reputation they have in the overlanding community already. Once I’d finally killed off the ATPs, I put on a set of the aforementioned ST Maxxs in the 255/80-17 “pizza cutter” size. Those tires also impressed with their nearly silent and steady-tracking road manners. I sold the Tacoma before I really had a chance to put them to work, but knew I’d be giving Cooper another shot. And with four of my guys also running the ST Maxx series, Cooper has been doing No Known Boundaries well. So a set of 315/75-16 Pros was mounted to the FJ, and the rest is sure to become history.
I suppose we should actually start the review with road manners, since we spend so much time on pavement, much to our collective chagrin. With no sugar-coating, these are aggressive tires and you’ll know it. Road noise is actually pretty impressive all things considered; the hum of the tires is not noticeable with the windows closed. But once you roll the windows down on a county road at 40 MPH, you’ll hear the distinct *WHOMM* sound. Moreover, you’ll feel these tires with a faint pulsing and rattle. With the stout sidewalls, and stiff compound, the Pros ride accordingly. They are heavy, and required quite a bit of weight to balance for me. Speaking strictly in terms of pavement performance, they are noticeably behind a Duratrac or ST Maxx. While road behavior is certainly the weak link in the Pro’s chain, this should not be taken as me slamming them. All things considered, I don’t actually dislike this tire on the highway. I put in 11 hours of windshield time throughout the AZ/NM/CO interstates and highways last week with no actual discomfort or grievance. But the STT Pro is no thief in the night, not by a longshot.
In more of an indictment of BFG, the STT Pro is actually more quiet than every set of their tires I’ve run, including the timeless KO. Driving on BFGs was akin to riding on a primitive stone wheel for me, so these qualms could certainly be more scathing.
OFF ROAD PERFORMANCE
So then, what of their performance in the fun stuff? Put simply, they really come alive in the backcountry. Aired down to 13 PSI, they glide over rocks that would otherwise have the rig bucking like a wild bronco. I engaged four wheel drive for one ledge climb, and other than that, their bite was instantaneous and consistent. The only time I lacked traction was climbing a 10 inch, gravel-covered shelf on said ledges. Putting the throttle down enough to walk the front tire over the shelf meant that the rear wanted to break lose on that gravel from a dead stop. Of course, a bit of momentum could’ve solved that. Instead, I just used the cheat button and walked it up at 1600 RPM.
Through sand, up gravel-littered hills, and over rocks of all sizes, these tires want to hug the terrain. And much like my previous experience with the ATP, they ate up the offroad challenges at full pressure as well. In 2WD, I was able to zip around the 6-inch-deep beach sand north of Santa Fe at full pressure. Sadly, I haven’t had a chance to bury them in any soft, white, frozen hydrogen yet. Colorado is experiencing an alarming and upsetting snow drought and heat wave that not only has very dangerous implications, but is hamstringing late fall/early winter activities severely. As such, I’ll have to follow up on their wet and snowy performance at a later date. The Pro is an M+S rated tire, but is not Severe Service Winter rated. While I don’t find that to be prohibitive personally, it should be noted that if your daily commute or activities will find you regularly traversing black ice, deep snow, and wet sleet, there are more appropriate options.
WHO IS THIS TIRE FOR?
People who plan on spending a good amount of time doing day runs or incorporating technical trails into their longer trips. If you’re familiar with Colorado trails, the STT Pro will be right at home on China Wall, Twin Cone, or Miner’s Gulch. It’s a tire for those looking to spend numerous days hammering the Moab area’s red rocks and dirt, or beat up their sliders in central Arizona’s playgrounds. If you don’t need to commute a million miles a day and prioritize your weekend warrior ability over your grocery-getting, they may very well suit you. In my opinion, the ideal candidate is looking for a 33”-37” tire on a rig with a healthy amount of suspension travel. They want to do overland trips or offroad trail runs in moderate technical terrain. They want to go places that Google won’t navigate them to, and enjoy airing down their tires, engaging their lockers, and earning their way to the destination the hard way.
WHO ISN’T THIS TIRE FOR?
Those on the fence about whether they need a more aggressive tire will likely find themselves reverting back to milder options. Coming from all season or light all terrains to a tire like this is likely going to be pretty jarring for novice offroaders or more mild drivers. It’s not realistic to expect most people to go around blaring Pantera at volume 30 like I do, so what I consider mild road noise may drive others insane if they’ve been driving late model crossovers/SUVs with soft rides. While it bridges the gap between standard all-terrains and weekend truck mudders, the Pro will be wasted on graded fire roads and in developed campgrounds. Those who aren’t planning on pinstriping their rigs or acquiring trail damage will be better served by softer compounds and lighter construction.
CLOSING THOUGHTS (FOR NOW)
As I said, the Goodyear Duratrac has been my gold standard for some time. Its combination of respectable off-road performance, delightful road manners, ease of balance, and tread life has not yet disappointed me. However, I have quickly become a fan of Cooper’s tires since making the move over to Toyota vehicles. As such, I wanted to see if I could find a tire that mimicked the Duratrac while expanding on its strengths off-road, as well as being constructed with a more durable sidewall and tread material. Whether the STT Pro will win me over remains to be seen. But I have thoroughly enjoyed these tires so far. More to come after some more miles, some more trail, and HOPEFULLY, some damn snow.