Discoverer AT3 4S

About the Cooper Discoverer AT3 4S

All-Weather All-Terrain Passenger Light Truck/SUV tire.

Features

* Silica based all-weather compound coupled with Secure-Grip all-terrain tread design* Ultra durable compound along with rugged tread design* Snow groove technology* Aqua Vac channels* Micro-gauge zigzag sipes in all tread blocks* Carries the Three-Peak Mountain Snowflake (3PMSF) symbol* 65,000 Mile Treadwear Protection* Standard Limited Warranty* Free 45-Day Road Test

Benefits

* Enables tires to adapt to a range of environments and temperatures, be it wet or dry, hot or cold* Bolsters strength against sharp gravel and dirt roads while extending paved road wear* Traps snow in tread to provide superior snow on snow traction* Improve the tires resistance to hydroplaning* Provide increased vehicle stability and control and increase wet/dry traction, while reducing stone retention and drilling* Meets the required performance criteria for Use in Severe Snow Conditions

Understanding the 275/60R20 size

In the size code 275/60R20, 275 is the section width in millimetres (about 10.8"). 60 is the aspect ratio — the sidewall height is 60% of the width, or roughly 165 mm. R20 means radial construction on a 20-inch wheel, giving an approximate overall diameter of 33".

The load index 115 means each tire supports up to 2,679 lbs — about 10,716 lbs across a full set of four. The speed symbol T certifies the tire to 118 mph under its rated load. Always match or exceed the load index and speed rating listed on your vehicle's door-jamb placard.

What the Cooper Discoverer AT3 4S is built for

It carries the three-peak mountain snowflake (3PMSF) symbol, meaning it passed a standardised severe-snow traction test.

Tread life and grip ratings

This tire carries a UTQG rating of 620 A B. The treadwear grade of 620 is a relative durability score — a grade of 200 is expected to last roughly twice as long as a grade of 100 under the same controlled test. Traction grade A measures straight-line wet stopping grip (AA is highest, then A, B and C). Temperature grade B reflects heat resistance at sustained speed (A is highest).

Price and value

At $173.99 per tire, a full set of four costs $695.96. That is about 20% below the average price of the 140 tires we stock in this size. Backed by a 65,000-mile treadwear warranty, that works out to roughly $10.71 per 1,000 miles across the set.