Cooper Discoverer STT PRO review
Cooper Tire knocks one out of the park with their new Discoverer STT PRO series light truck and SUV tire
I don’t normally do best light truck and SUV tire reviews, but I had the chance to field test Cooper’s next generation light truck and SUV tire and I came away mighty impressed. The new Discoverer STT PRO took three years to develop and incorporates a unique tread block design, a protective 3-ply belting configuration, rim flange protectors (to protect your alloy wheels), side biter cleats, and a flex groove.
The Discoverer STT PRO is perfect for use in off-road use, but that’s not why I’m reviewing it—most of my readers don’t do off-roading. But they do use their light trucks and SUVs for work and family. If you’re a tradesperson who relies on your truck to bring home the bacon this tire will get you to the jobsite and back every day. Here’s what I learned about the new Discoverer STT PRO.
1) It’s not easy being mean
Look, it’s not hard to design a mean looking tire. Just space big honkin’ tread blocks around the tire, mount a few equally mean looking tread blocks on the sidewall and call it a day. But looking mean and acting mean are two different animals. It takes quite a bit of engineering know-how to design a tread block that loads and ejects mud but loads and holds snow (snow-on-snow provides more traction than rubber on snow ). Cooper engineers solved that problem with unique mud scoops and ejection dimples. The scoops, well, ah, scoop mud into the void. As the mud packs into the void, it traps air in the dimples. As the tire turns out of the mud, the air pockets eject it. In winter, the same tread block features compact snow and hold it in place. Brilliant.
The engineers faced similar challenges with the side biter cleats. They’re designed to dig into a rut and pull you out. But they also have to resist cutting and chipping. Designing a side biter that
digs into mud and provides traction against rock and boulder, but doesn’t tear off the tire is a major coup and Cooper has pulled this off as well. The Discoverer STT PRO pulled me right out of deep mud ruts and helped me climb up rocky slopes. After eight hours of tortuous driving, the side biters had no damage whatsoever.
2) Ply me to the moon
Economy truck tires are built with two plies. Premium truck tires have three. The additional ply strengthens the sidewall significantly. But here, Cooper has taken a different approach by running the third ply at an angle to the two radial plies. The angled ply provides an extra measure of sidewall stability and puncture resistance. Just what you need on a construction site.
3) Scrape rattle and roll
Ok, this alone isn’t a justification for buying the Discoverer STT PRO. But if you have alloy wheels on your truck or SUV and drive through construction sites with rocks and boulders, you know it’s easy to damage your pretty wheels. I don’t know why other tire makers haven’t made this standard on their tires, but really, how much extra effort does it take to mold in a rim flange protector? Apparently it’s not that hard for the guys at Cooper. The raised rim flange protector is molded into the lower sidewall area, so it protects the wheel flange from rock damage. Problem solved.
4) It’s all about the bass, ‘bout that bass
Ok, you knew it was going to come down to noise, right? Well, it’s true—aggressive high void tread patterns make more noise than less aggressive tread designs. Light truck owners hate that deep bass hum/rumble at highway speeds that makes you think you’re driving a semi. Well, I drove these tires at highway speeds, and yes, they make noise. BUT, it’s a fraction of the noise levels I’ve experienced from other high-void tires. Honestly, I didn’t find the noise level at all objectionable.
5) Those sticks and stones
When you drive in gravel and rock, you’re going to push stones deep into the tread voids, and those stones can really tear up a tire. Some tire companies mold in stone ejectors to pop out the stones. Good idea. It works and Cooper uses that design on the Discoverer STT Pro as well. But they also take it one step further by angling the groove walls to prevent the stones from getting trapped in the first place. Not exactly rocket science, but pretty darn good tire science, dontchathink?
6) If I knew you were comin’ I’d have baked a cake
Developing just the right tire compound recipe to match the tread and expected driving conditions is, well, an art. Tire engineers have far more ingredients at their disposal today than just five years ago. So the Discoverer STT PRO is a blend of all the right ingredients to provide the best traction in mud, rain, ice, and snow, yet resist cutting and chipping on rocks and gravel. My congratulations to the chefs!
7) Yeah, this is where the rubber meets the road
You knew I was going to use that phrase somewhere in this review. But here’s the bottom line: Twelve journalists went into the mountains and woods. None of us were professional drivers. We drove our Jeeps for eight straight hours through grass, mud, streams, gravel, rocks, tree roots, and up and down steep inclines. None of us got stuck. No tires were punctured or damaged. The Jeeps were covered in mud and so were we. But the consensus was unanimous. These are darn good tires.
Congratulations Cooper Tire, the Discoverer STT PRO is a home run (I can’t believe I threw in a baseball analogy).
Posted on by Rick Muscoplat