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Cooper Tires
Cooper Tires COO Discoverer AT3 LT LT265/65R18/10
Cooper Tires COO Discoverer AT3 LT LT265/65R18/10
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Shop the Cooper Tires Discoverer AT3 LT 265/65R18 at ThreePiece.us — free shipping on every order, Affirm financing available, and fast delivery nationwide.
What 265/65R18 means
In the size 265/65R18, 265 is the section width in millimeters (10.43 in), 65 is the aspect ratio — the sidewall stands 65% as tall as the tire is wide, or 172.2 mm (6.78 in) — R denotes radial construction, and 18 is the wheel diameter in inches. That works out to an overall diameter of about 31.56 inches, turning roughly 639 revolutions per mile. Overall diameter is what matters for speedometer accuracy and clearance when you change sizes, so compare it — not just the width — against your current tire.
The service description on this tire decodes to a load index of 122 — a maximum load of 3,307 lbs per tire. The speed symbol R corresponds to a maximum sustained speed of 106 mph.
Specifications
| Size | LT265/65R18/10 |
| Tire Type | All Terrain |
| Service Description | 122R |
| Load Index | 122 |
| Speed Rating | R |
| Load Range | SL |
| Section Width (mm) | 265 |
| Aspect Ratio | 65 |
| Overall Diameter (in) | 31.54 |
| Tread Depth (/32") | 16 |
| Warranty | 60K |
Frequently asked questions
What warranty does the Cooper Tires Discoverer AT3 LT carry?
The manufacturer's warranty on this tire is 60K.
What does 122R mean on the Cooper Tires Discoverer AT3 LT?
122R breaks down as load index 122 — rated for 3,307 lbs per tire — with an R speed rating, good for a maximum sustained 106 mph.
What kind of tire is the Cooper Tires Discoverer AT3 LT?
The Cooper Tires Discoverer AT3 LT in 265/65R18 is a all terrain tire.
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Shop all 265/65R18 tires, see every Cooper Tires Discoverer AT3 LT size, explore all terrain tires, or view all tires at ThreePiece.us.
- BRAND:
- Cooper Tires
- Model:
- COO Discoverer AT3 LT
- Size:
- LT265/65R18/10
- Aspect Ratio:
- 65
- Load Index:
- 122
- Load Range:
- SL
- Section Width:
- 265
- Service Description:
- 122R
- Speed Index:
- R
- Temperature:
- N/A
- Tire Rim Diameter:
- 31.54
- Tire Type:
- All Terrain
- Traction:
- N/A
- Tread Wear:
- N/A
- Tread Depth:
- 16
- UQTG:
- N/A
- Warranty:
- 60K
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