Cooper
Discoverer AT3 4S All-Terrain Tire
- Fits 275/65R18
- All-terrain (A/T)
- All-weather
- 3PMSF (winter rated)
- Load/speed 111T
Confirm your factory (OE) tire size with the sources behind it, filter the CarCareTruth-scored tires that fit by how you drive, and shop your exact size on Amazon. The sticker inside your driver's door is always the final word.
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This generation came with more than one factory size, depending on trim and wheel package. Pick the size that matches your car to see and shop the tires that fit it. Sizes marked amber are used by some trims only and are not confirmed for your specific vehicle, so read the white sticker inside your driver's-door jamb to confirm yours.
Your exact size is printed on the driver's-door sticker. If it differs from what is shown here, trust the sticker.
Verified from 2 sources
Pick a driving style to narrow the list. This filters and re-sorts the tires that fit your size; it never hides a tire that fits.
Shows every tire that fits your size, ranked by CarCareTruth score. Pick a driving style to narrow it down.
Ranked by the CarCareTruth score: tread quality, ingredient health, and environmental footprint. The number is ours and we show the breakdown; we do not lab-test tires or call one model the outright best.
Cooper
Nokian Tyres
Toyo Tires
Bridgestone
Yokohama
BFGoodrich
Falken
General Tire
Mickey Thompson
Nitto
We don't lab-test tires. We match your driving to the right tire type, then point you to the highest owner-rated options in your size. For independent, model-by-model test data, Tire Rack and Consumer Reports test specific tires and publish the results.
Every tire stamps a UTQG treadwear grade on the sidewall, but the number is self-reported by the manufacturer against its own reference tire. That makes it a rough class signal for how long a tire might last, not a head-to-head ranking. A 700 from one brand and a 700 from another do not promise the same mileage. Use it to compare tires of the same type from the same maker, and treat the type itself as the bigger signal.
The UTQG traction grade (AA, A, B, C) measures straight-line wet braking only, not cornering or snow grip. Almost every modern tire is A or AA, so it rarely separates good tires from great ones on its own.
Once the tires are on, these are the CCT-scored products that keep them looking and lasting their best.

Tire dressing (shine + UV protection)
New tires look their best with a dressing that also shields the rubber from sun cracking. Pick a water-based one for a satin, non-greasy finish.

Tire cleaner (prep before dressing)
Dressing only sticks to clean rubber. A dedicated cleaner strips old brown dressing and road grime so the new coat lasts.

Tire inflator (keep them at spec)
Underinflated tires wear faster and waste fuel. A portable inflator lets you hit the door-placard pressure in your driveway.

Torque wrench + socket set (install day)
If you mount or rotate tires yourself, a torque wrench is the difference between a safe wheel and a warped rotor or a loose lug.
Look up your car's lug-nut torque spec in the owner's manual before you install, then tighten in a star pattern with a torque wrench. Re-torque after the first 50 to 100 miles. Most passenger cars land between 80 and 100 lb-ft, but always use your car's exact number.