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Cooper
Cooper Discoverer Enduramax 225/55R18XL 102H - 166300007
Cooper Discoverer Enduramax 225/55R18XL 102H - 166300007
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The Cooper Discoverer Enduramax in 225/55R18 ships free from ThreePiece.us, with Affirm financing available at checkout and fast delivery from a nationwide warehouse network.
What 225/55R18 means
In the size 225/55R18, 225 is the section width in millimeters (8.86 in), 55 is the aspect ratio — the sidewall stands 55% as tall as the tire is wide, or 123.8 mm (4.87 in) — R denotes radial construction, and 18 is the wheel diameter in inches. That works out to an overall diameter of about 27.74 inches, turning roughly 727 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 102 — a maximum load of 1,874 lbs per tire. The speed symbol H corresponds to a maximum sustained speed of 130 mph.
Load Range E corresponds to a 10-ply rating.
Specifications
| Size | 225/55R18XL |
| Tire Type | All Season |
| Service Description | 102H |
| Load Index | 102 |
| Speed Rating | H |
| Load Range | Extra Load |
| Section Width (mm) | 225 |
| Aspect Ratio | 55 |
| Overall Diameter (in) | 27.76 |
| Tread Depth (/32") | 10.5 |
| Treadwear | 640 |
| Traction Grade | A |
| Temperature Grade | A |
| UTQG | 640AA |
| Warranty | 60K |
Frequently asked questions
What does 102H mean on the Cooper Discoverer Enduramax?
102H breaks down as load index 102 — rated for 1,874 lbs per tire — with an H speed rating, good for a maximum sustained 130 mph.
What kind of tire is the Cooper Discoverer Enduramax?
The Cooper Discoverer Enduramax in 225/55R18 is a all season tire.
What are the treadwear and warranty ratings on the Cooper Discoverer Enduramax?
This tire carries a treadwear grade of 640, traction grade A, temperature grade A under UTQG. The manufacturer's warranty is 60K.
Keep shopping
Shop all 225/55R18 tires, browse Cooper tires, see every Cooper Discoverer Enduramax size, or view all tires at ThreePiece.us.
- BRAND:
- Cooper
- Model:
- Discoverer Enduramax
- Size:
- 225/55R18XL
- Aspect Ratio:
- 55
- Load Index:
- 102
- Load Range:
- Extra Load
- Section Width:
- 225
- Service Description:
- 102H
- Speed Index:
- H
- Temperature:
- A
- Tire Rim Diameter:
- 27.76
- Tire Type:
- All Season
- Traction:
- A
- Tread Wear:
- 640
- Tread Depth:
- 10.5
- UQTG:
- 640AA
- Warranty:
- 60K
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