The Mickey Thompson Deegan 38 AT and the Cooper Discoverer AT3 XLT, being powerful all-terrain tires allow you to tackle a lot of different kinds of terrains including tar. Though there are some key factors to consider for both. Let me make them clear for you.
In my expert opinion as a tire engineer, the Mickey Deegan 38 AT although offers better off-road traction, it’s on-road grip is very lacking. The Cooper AT3 on the other side, gives you superior performance on wet and winter terrains, as well as, amazing tread life. Though its fuel efficiency is on par to its competitor, if not lower.
Table of Contents
Sizes Facts
Cooper Discoverer AT3 XLT comes with 32 sizes in total 15 to 20 inches rims, with following specs.
- Speed ratings of either R or S.
- Load ratings: C, D, E and F.
- Weight range: 44 lbs to 70 lbs.
- Tread depth: 16.5 or 17/32″ in all sizes.
- All sizes have 60k miles warranty.
- Inner Construction: 2 ply polyester, 2 steel belts, 1 ply nylon.
Detailed Review of Cooper AT3 XLT.
On the other side, the Mickey Thompson Deegan 38 A/T provides you with 35 total sizes in 15 to 22 inches, having following specs:
- Speed ratings: R, S and T.
- Load range: SL, XL, C and E only.
- Weight range: 30 to 63 lbs.
- Tread depth range: 12 to 17/32″.
- Warranty: 55k miles for LT, and 60k for non LT sizes.
- Inner Construction: 2-ply steel, 2-ply polyester, 2 ply nylon.
Make sure you know exactly what’s speed rating: https://tiredriver.com/speed-rating-on-tires/
Tread Design
Let me start here with Cooper Discoverer AT3 first.
Cooper’s boy offers a 5 rib design having 4 ordinary circumferential grooves (that you mostly see on highway oriented tires).
And to further improve traction, these ribs have lugs running in pairs, having reinforced foundations underneath, allowing for stable on-road stability and steering response.
The middle most rib is slightly thicker/wider blocks, basically made to maximize rubber to ground contact. This enhances dry grip, whereas on wet, the lugs have full depth interlocking sipes and sharp chamfered edges, helping traction efficacy.
The surrounding blocks have similar features except for snow vices which are basically sharp edges (toothed), which offer snow traction.
Moving towards the shoulders, they show the same stuff, though their outer margins are staggered, and they get to make thicker sidewall lugs in comparison.
Moving towards the the Mickey Thompson Deegan 38 AT, this tire also offers a very on-road oriented design, with lugs structured very much like the Cooper AT3.
First off, like it’s competitor, the tread features a 5 rib design, with 3 ribs in the middle making 4 longitudinal channels.
Out of these circumferential grooves, the outer two are slightly wider.
Moreover, on all these ribs, just like it’s counterpart, the blocks run in pairs, as they are joined up with each other with ridges, in a similar fashion.
Though they carry slightly more biters and different notches, as they are not as “squared off”.
The central most lugs form a S shaped design, whereas on surrounding ribs, lugs have sharp chamfered edges and offset sides.
Though the shoulder lugs on this tire are a bit different. They have wider gaps in between then, don’t have snow vices, and their outer margins are also missing mud scoops, and sidewall lugs.
And yes, the overall siping of the tire is also rectilinear whereas on Cooper AT3 features interlocking structure.
Snow Performance
Winter performance depends on the tire’s gripping abilities on multiple terrains, including ice, on-road snow, and deeper fluffy tracks.
And with 3 peak mountain snowflake rating, here, the Cooper Discoverer AT3 XLT shows up with better results. The tire has a softer compound so its biters stay pliable even with freezing temperatures, it outer grooves have snow vices in them, which grab the snow particles. And for deeper terrains, its staggered shoulders provide scooping.
Mickey Thompson Deegan 38 AT on the other side is missing all these features, and with simple rectilinear sipes, the tire can’t grip on all types of terrains in a better way. And this goes especially for ice, where the tire is straight up dangerous.
Wet Traction
Improved wet traction is only attainable with effective water evacuation, which is facilitated by wet grip and resistance to hydroplaning. Let’s explore each element separately.
Wet Grip
A tire that combines siping and flexibility in its tread pattern ensures a better grip on wet roads. These features work in unison to clear water rapidly (which is the only way to grip, as water is an incompressible liquid).
And considering these factors, it can be seen why the Mickey Thompson Deegan 38 AT does so poorly on wet roads. The tire lacks the softness needed in the tread, and it’s sipes with rectilinear structure already get pretty stiff when it corners, brakes or accelerates.
Cooper Discoverer AT3 XLT on the other side, does the opposite, it’s sipes are more in number, they have a wave-like structure, and it’s overall tread is also much supple.
All of these ensure better effectiveness of its sipes, resulting in the tire’s superior wet grip.
Hydroplaning
The slow removal of water from the tires’ grooves is the root cause of aquaplaning and decreased wet traction. Though with both tires having a voided enough design, it’s not an issue with them.
Nonetheless, if you have to pick one over the other here, I’d suggest, the Cooper AT3, mainly because of it’s ability to create better negative pressure, again thanks to it’s softer compound.
The Deegan 38 AT on the other hand, shows up with slightly slower float speeds (maximum speed with which a tire can move over water without floating), even with it’s (slightly) wider shoulder voids.
Dry Traction
When determining the dry performance of an all-terrain tire, traction, steering, and cornering ability are all critical components to consider. Let’s explore each of these elements in more detail.
Dry Grip
Dry grip or directional grip is a measure of a tire’s traction while driving straight ahead and it gets determined through assessments of braking distance and acceleration time.
And when a tire is stopped (from a specific distance), it’s moving inertia, and overall footprint comes in to action. That’s why it makes sense why Mickey Thompson Deegan 38 AT is better.
It’s lighter structure stops quicker, and with more rubber to road contact, it’s blocks create more rolling friction in comparison.
Cooper Discoverer AT3 XLT on the other side, although is pretty packed up too, it still lacks overall, due to it’s wider grooves, and greater weight, which form a larger moving momentum (harder to stop as quick).
So overall, its safe to say, that both tires are good daily driving all-terrain tires, (on dry roads).
Lateral Grip
As the tire corners, it’s whole weight gets shifted towards the shoulders, and so with Cooper AT3 forming a greater contact with the ground form there provides better handling abilities.
Mickey Thompson Deegan 38 AT on the other side, has wider lateral grooves between the shoulder lugs, though its more affecting part here is it’s slower steering response.
Even though the tire has a slightly stiffer rubber composition, it’s lugs don’t have reinforced foundations underneath, so they get to flex more on corners, as the tire turns, and this lowers the overall steering response and sensitivity.
Tread Noise
Tread noise gets generated by two ways, from the rolling of the tire with different kinds of surfaces, and with air particles hitting the tread walls.
And so considering both it’s a tie between the two.
The Mickey Thompson Deegan 38 AT has open shoulder blocks in comparison, which allows more air particles to come in and hit the walls, creating noise form there, whereas the Cooper AT3 with it’s softer compound and greater tread depth creates similar decibels levels with its in-groove resonance formed with it’s rolling against the road.
If it’s confusing, understand these two main key things:
- Softer tires, like Cooper AT3 produce more echoing between the tread voids, meaning noise bounces off more on this tire in comparison.
- And also as the tire rolls, most of air particles come in through the shoulder voids.
On-Road Vibrations
Noise has it’s place, but mostly the overall comfort of a tire is largely associated with the its’ ability to soak up the bumps off the roads, and here Cooper Discoverer AT3 XLT is doing a better job with its softer tread, and greater tread depth.
It’s malleable lugs, absorb the shocks of the road better, and with deeper tread voids, they provide a thicker layer of rubber between you and the road, so imperfections of the road have more area to settle down.
Mickey Thompson Deegan 38 AT with it’s harder compound feels stiffer in comparison.
Off Road Abilities
Each terrain type on rugged paths requires specific skills from tires, that’s why I evaluated them in all of these off-road tracks.
On Mud
In order to navigate through mud with ease, all-terrain tires need to be designed with a tread pattern that features larger grooves, enabling quick evacuation of mud and reducing the risk of “packing”.
And considering the performance of both tires, I’ve rated them both equally here. Though they provide traction in very different ways.
The Cooper Discoverer AT3 XLT although has closed up shoulder lugs, and middle section, not allowing mud to leave out quickly especially form sideways, it’s thicker staggered shoulder scoops, and sidewall lugs still provide good enough traction with “paddling”. This throws the mud backwards and yields forward motion as a result.
On the other side, the Mickey Thompson Deegan 38 AT, although is missing with serrated edges, and lugs on sidewalls, it’s superior central evacuation capabilities provides this tire with similar overall traction abilities as its counterpart.
Side Note: I covered how all-terrain tires are on mud in detail, here: https://tiredriver.com/are-all-terrain-tires-good-on-mud/
Rocks
Both tires with longitudinal arrangement of the blocks really lack in providing lateral traction. Though still, out of them both, you’d be better off, when it comes to climbing rocks, with Cooper AT3.
This is because at least this tire provides you thick sidewall lugs, and serrated shoulder edges, which with lowered PSI, get to enhance the tire’s overall footprint, and grab the rocky surface with a better stability.
Mickey Thompson Deegan 38 AT on the other side, could use some biters towards edges, so its lacking here.
On Sand
Driving on sand calls for reducing the air pressure of the tire to improve performance on soft surfaces. This is because this allows for molding of the tread lugs, against the sand, enhancing overall footprint, and with it tire’s floating abilities, as digging on sand is the worst for traction here.
That’s why Mickey Thompson Deegan 38 AT with missing sidewall lugs, and sharper outer edges, get to be more prone to digging, comparatively, where it’s stiffer compound isn’t helping that as well.
Cooper Discoverer AT3 XLT on the other side, with softer compound and larger sidewall lugs provide much better contact patch, as these lugs spread out with lowered air pressure.
To Conclude
So let me conclude all of it here quickly.
The Mickey Thompson 38 AT provides superior dry grip, and is great off-road on muddy terrains. Whereas the Cooper AT3 does better with wet grip, comfort, fuel and tread life, and off-road, yields superb sand traction.
