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Cooper Tires
Cooper Tires COO Discoverer AT3 LT LT275/70R17/10
Cooper Tires COO Discoverer AT3 LT LT275/70R17/10
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The Cooper Tires Discoverer AT3 LT in 275/70R17 ships free from ThreePiece.us, with Affirm financing available at checkout and fast delivery from a nationwide warehouse network.
What 275/70R17 means
In the size 275/70R17, 275 is the section width in millimeters (10.83 in), 70 is the aspect ratio — the sidewall stands 70% as tall as the tire is wide, or 192.5 mm (7.58 in) — R denotes radial construction, and 17 is the wheel diameter in inches. That works out to an overall diameter of about 32.16 inches, turning roughly 627 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 121 — a maximum load of 3,197 lbs per tire. The speed symbol R corresponds to a maximum sustained speed of 106 mph.
Specifications
| Size | LT275/70R17/10 |
| Tire Type | All Terrain |
| Service Description | 121R |
| Load Index | 121 |
| Speed Rating | R |
| Load Range | SL |
| Section Width (mm) | 275 |
| Aspect Ratio | 70 |
| Overall Diameter (in) | 32.17 |
| Tread Depth (/32") | 17 |
| Warranty | 60K |
Frequently asked questions
What does 121R mean on the Cooper Tires Discoverer AT3 LT?
121R breaks down as load index 121 — rated for 3,197 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 275/70R17 is a all terrain tire.
What warranty does the Cooper Tires Discoverer AT3 LT carry?
The manufacturer's warranty on this tire is 60K.
Keep shopping
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:
- LT275/70R17/10
- Aspect Ratio:
- 70
- Load Index:
- 121
- Load Range:
- SL
- Section Width:
- 275
- Service Description:
- 121R
- Speed Index:
- R
- Temperature:
- N/A
- Tire Rim Diameter:
- 32.17
- Tire Type:
- All Terrain
- Traction:
- N/A
- Tread Wear:
- N/A
- Tread Depth:
- 17
- UQTG:
- N/A
- Warranty:
- 60K
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