Both Cooper Discoverer ST Maxx and the Goodyear DuraTrac are great rugged-terrain options, though they are marketed as all-terrains. That’s why you won’t get disappointed with them, especially on beaten off-road paths, though their daily commute is also impressive. Yet, it often requires lots of time and effort to make the right decision. Let me save you some of that.
In my professional opinion as a tire engineer, the Goodyear Wrangler Duratrac showed better performance on both dry and wet roads (during my tests). Moreover it’s fuel and tread economy is also much greater here, along with winter performance. The Cooper ST Maxx on the other side, does okay on dry roads, and off-road yields superior traction on rocky terrains, though lacks in mud and sand with it’s missing sidewall lugs.
Table of Contents
Tire Facts
Starting with Goodyear Wrangler Duratrac
- The tire comes in 15 to 22″ rim sizes.
- They have weight range: 35 to 68 lbs.
- Speed rating: Q, S, P, and T.
- Load rating goes up to F.
- Tread depth: 16/32″ to 18/32″.
- 3PMSF and M+S winter ratings on all sizes.
- 50k miles tread wear warranty (on P metric sizes only).
- 16 installable Stud-able lugs (only LT sizes).
On the other side, the Cooper Discoverer ST Maxx comes with following specs:
- Total sizes: 47.
- Rim sizes available: 15 to 20 inches.
- Speed ratings: Only Q.
- Load ratings: C to F.
- Weight range: 38 to 70 lbs.
- Tread depth: 18.5/32″ on all.
- No 3PMSF ratings available.
- No treadwear warranty.
Tread Appearance
Both tires are although equally aggressive, the Goodyear Duratrac still provides you with some extra features. So let me discuss this tire first, starting from the middle.
Compared to the outer (shoulder lugs), the middle part of the tread contains smaller lugs, but they have ample biters in the form of saw-toothed edges and chamfered sides, along with full depth interlocking siping.
And where all these features yield off road traction, the reinforced foundations underneath all these blocks also ensures strong grip on pavements, even though they are surrounded by wild circumferential groove rings.
(These outer longitudinal channels basically are very capable as they have small biter in them, and this offer amazing off-road traction, as you’d see in the upcoming performance topics).
Moving towards the shoulders, the lugs are bigger here, and carry more aggressive interlocking siping pattern, but other than that, the rest of the features are similar, they have sharp edges and reinforced foundational supports, to name a few.
On the outer margins they make staggered edges, and their sidewall lugs are also pretty thick enough, though not visible here.
Speaking of which, since the image does not show a tire with LT size, you are not seeing any studable lugs.
On the other side, the Cooper Discoverer ST Maxx provides you with, equally, as aggressive design.
The tire basically form a very self cleaning symmetric tread, forming both, lateral and longitudinal orientation of the grooves.
The central lugs form straight forward slanted lateral tread voids, connecting with the outer circumferential channels, which then connect with the shoulder voids, allowing mud, dirt, stones and so on, to easily pass though without lodging in.
Moving towards the shoulders, you get a slightly more aggressive structure there, as these studable lugs get to carry sharp chamfered biters, and stepped edges, and have bold stone ejectors in between.
They also make very biting sidewalls where although they don’t have proper mud scoops, each lug is staggered on itself.
This combined with the blocks there, you get ample off-road bite (especially when you run the tire with lowered air pressure).
Internal Make-Up
The demands of rough terrains, require off-road tires to be tough, making durability a critical aspect. And to increase durability, nearly all of them are equipped with cut-resistant rubber and deep tread voids.
Though the overall strength is still primarily determined by their internal construction, particularly on sidewalls.
And considering both tires, it can be seen why the Cooper Discoverer ST Maxx is more resistant to puncture, in comparison.
It comes with 3 ply polyester, with third layer at an eight degree bias angle (enhancing strength further), which is then further reinforced with 2 steel belts and a single nylon cap ply.
The Goodyear Duratrac on the other side, only comes with 2 ply sidewalls, though it provides one extra cap ply, just so you know, (though its still a weaker tire overall).
Fuel And Tread Usage
Both these metrics are closely related, as they are both affected by the tire’s rolling resistance, which is then impacted with its weight, structure, and tread composition.
That’s why being a more aggressive tire, the Cooper Discoverer ST Maxx gets to put more pressure on it’s lugs, and they rub off the surface with greater friction.
It’s lugs are basically more spaced apart, so even though its weight is only slightly heavier, each of it’s tread blocks still carries more (divided) weight upon itself.
This causes faster burning rate, negatively affecting the tread life, and increases rolling resistance which reduces fuel economy.
Goodyear DuraTrac on the other hand features reinforced foundations underneath it’s lugs, and so it’s lugs stay firm, allowing for superior fuel efficiency and slowed down tread wear.
I explained it more in:
Do A/T tires wear faster?: https://tiredriver.com/do-all-terrain-tires-wear-faster/
Wet Traction
A secure grip on wet roads is achieved through the evacuation of water, which is basically done with the help of sipes and grooves.
Sipes are slit on the tread blocks, which soak up the water particles, so the rubber can grip the (relatively dry) surface of the (cleared) road.
That’s why with a lot more in number of these sipes, the Goodyear Duratrac comes out with better gripping values.
Though both tires show up with similar hydroplaning resistance which has to do with water evacuation at a macro level, done with the help of grooves.
Highway Performance
When evaluating the dry performance of these tires, I closely monitored their directional and lateral traction. Let me share the results with you.
Directional Grip
Directional grip, as the name states, is the tire’s traction when rolling straight. It depends on the tire’s footprint offering and lugs arrangement, and gets calculated by braking distances (mostly).
And considering all factors, it can be seen why Goodyear Duratrac shows up with better results here. The tire comes with much closer blocks arrangement in the middle (where most of the weight gets focused on). And they provide better rubber to road contact.
The Cooper STT Maxx on the other hand, isn’t able to form as consistent of a rubber to road connection, as it’s counterpart. It’s wider lateral grooves literally come in the way, limiting its overall grip.
Dry Handling
This performance metric is further divided in to 2 parts, sideways grip, and steering response. And although both tires aren’t so great in them, you still see better results on Goodyear Duratrac. Let me explain why.
This tire besides having a relatively closer lugs arrangement, comes with dual compound with harder foundations.
The closeness of lugs brings about superior grip, while with dual compound, the tire isn’t as susceptible to under/over steering, as the Cooper ST Maxx.
Road Noise
Unwanted noise is generated from the air flow, where most of it enters and exits through the outer ribs of the tread (as the tire rolls).
Basically, what we call “tread noise” is produced by 2 things:
- When air particles hit the thread.
- And when the impact making noise bounces off (think of it as echoing).
And considering both, the Goodyear Duratrac still does better here, even though it’s not a “quiet” tire by any means.
Basically it deals with entering noise with its superior (in comparison) pitch sequencing. It’s a technology that involves changing the shapes of the blocks slightly (from one another), so they could form different tones at various places, when air particles hit them. Those variations in tones help in canceling down the noise levels.
The Cooper ST Maxx, on the other side, has wider outer voids, allowing more air to come in, and its pitch sequencing technology isn’t that effective either.
Snow Traction
When it comes to winter performance for off-road tires, there are two main types of terrains, on-road/packed up snow/ice, and deeper fluffy snow.
And considering all, I would have to go with Goodyear Duratrac. Mainly because of its tractive grooves.
As discussed in the tread pattern section, the tire has mini tread blocks (with biters) embedded within the base of the tread voids. And these help in holding on to the trapped snowflakes.
This trapped snow then connects with other snow particles (on the ground) and provide greater rolling grip.
Think of it this way. The snowflakes have unique arms, and they tangle on to each other, generating greater friction. That’s why we have a phrase the snowball effect.
Cooper Discoverer ST Maxx on the other side is not that efficient in holding on to the snow like its counterpart. That’s why it doesn’t have the 3 peak mountain snowflake rating like the Duratrac.
Though I do like the fact that it offers studable lugs, just like the Duratrac, so both tires can be good enough on ice as well.
Off Road Traction
When it comes to off-road driving, some terrains are manageable, while others can be a real struggle. Let’s inspect all of these one after another.
Rocky Terrains
A tire capable of providing, strong grip in all directions, along with durability is your best bet for rocks.
That’s why with a more powerful inner construction, Cooper Discoverer ST Maxx offers a more confidence inspiring ride.
Furthermore the tire also features a relatively softer compound and has wider grooves. And these allow the tire to chew the rocky surface with a greater force.
Goodyear DuraTrac on the other side, although features a spacious design as well, its lugs aren’t that malleable compared to Cooper. So their bite isn’t as strong.
Though the tire does offer better sidewalls, and with lowered air pressure, they offer almost similar climbing abilities (subjectively speaking).
Sandy Terrain
Driving on sand can be tricky, that’s because, besides needing experienced skills in driving, you are also required with a lighter tire, capable of offering better contact patch to connect with the sand.
And here although it may seem surprising, the Cooper Discoverer ST Maxx is lacking overall, due to it’s missing (aggressive-enough) lugs on the sidewalls, which is very odd as the tire comes in the rugged terrain category.
In fact, in the list of hybrid tires, it’s having the least aggressive sidewall design, you’d see.
Goodyear DuraTrac on the other side, takes the upper hand by offering greater rubber to sand connecting abilities.
Also Read –
Are A/T tires good in sand: https://tiredriver.com/are-all-terrain-tires-good-on-sand/
Muddy Trails
The performance of all-terrain tires in mud is often limited by their inability to evacuate mud quickly due to narrower grooves. Though that’s not really an issue with these hybrid tires, having mud-terrain tires like shoulders.
They evacuate the mud out quickly so they’re not susceptible to getting packed like less aggressive tires.
Though out of both (after a lot of testing), I still landed on Goodyear Duratrac, to be a better choice here.
This is because it’s features a narrower section width (considering all sizes, and taking the average). And is able to slash through the thick mud in a better way, while it’s in-groove biters digest the mud down so it can leave out easily.
Conclusion
Out of both tires, the Cooper Discoverer ST Maxx gets to take the back seat when it comes to on-road performance. The tire lacks in offering ample wet and dry grip, fuel efficiency, comfort and tread life.
Though it shines off-road especially on gravely and rocky terrains.
The Goodyear Durtrac on the other side, is impressive on highways, especially wet ones, and it offers superior winter performance as well, thanks to its interlocking sipes.
And off-road its great with softer terrains such as mud and sand, but lacks in offering similar results in climbing rocks.
