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Cooper
Cooper Evolution H/T 255/55R18XL 109H - 171053006
Cooper Evolution H/T 255/55R18XL 109H - 171053006
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Shop the Cooper Evolution H/T 255/55R18 at ThreePiece.us — free shipping on every order, Affirm financing available, and fast delivery nationwide.
What 255/55R18 means
In the size 255/55R18, 255 is the section width in millimeters (10.04 in), 55 is the aspect ratio — the sidewall stands 55% as tall as the tire is wide, or 140.2 mm (5.52 in) — R denotes radial construction, and 18 is the wheel diameter in inches. That works out to an overall diameter of about 29.04 inches, turning roughly 694 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 109 — a maximum load of 2,271 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 | 255/55R18XL |
| Tire Type | All Season |
| Service Description | 109H |
| Load Index | 109 |
| Speed Rating | H |
| Load Range | Extra Load |
| Section Width (mm) | 255 |
| Aspect Ratio | 55 |
| Overall Diameter (in) | 29.13 |
| Tread Depth (/32") | 12 |
| Treadwear | 600 |
| Traction Grade | A |
| Temperature Grade | B |
| UTQG | 600AB |
| Warranty | 60K |
Frequently asked questions
What are the treadwear and warranty ratings on the Cooper Evolution H/T?
This tire carries a treadwear grade of 600, traction grade A, temperature grade B under UTQG. The manufacturer's warranty is 60K.
What does 109H mean on the Cooper Evolution H/T?
109H breaks down as load index 109 — rated for 2,271 lbs per tire — with an H speed rating, good for a maximum sustained 130 mph.
What kind of tire is the Cooper Evolution H/T?
The Cooper Evolution H/T in 255/55R18 is a all season tire.
Keep shopping
Shop all 255/55R18 tires, browse Cooper tires, see every Cooper Evolution H/T size, or view all tires at ThreePiece.us.
- BRAND:
- Cooper
- Model:
- Evolution H/T
- Size:
- 255/55R18XL
- Aspect Ratio:
- 55
- Load Index:
- 109
- Load Range:
- Extra Load
- Section Width:
- 255
- Service Description:
- 109H
- Speed Index:
- H
- Temperature:
- B
- Tire Rim Diameter:
- 29.13
- Tire Type:
- All Season
- Traction:
- A
- Tread Wear:
- 600
- Tread Depth:
- 12
- UQTG:
- 600AB
- Warranty:
- 60K
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