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Michelin
Michelin Primacy Tour A/S 245/45R18XL 100H - 55540
Michelin Primacy Tour A/S 245/45R18XL 100H - 55540
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Looking for a 245/45R18 all season tire? The Michelin Primacy Tour A/S is available now at ThreePiece.us with free shipping on every order and Affirm financing at checkout.
What 245/45R18 means
In the size 245/45R18, 245 is the section width in millimeters (9.65 in), 45 is the aspect ratio — the sidewall stands 45% as tall as the tire is wide, or 110.2 mm (4.34 in) — R denotes radial construction, and 18 is the wheel diameter in inches. That works out to an overall diameter of about 26.68 inches, turning roughly 756 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 100 — a maximum load of 1,764 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 | 245/45R18XL |
| Tire Type | All Season |
| Service Description | 100H |
| Load Index | 100 |
| Speed Rating | H |
| Load Range | Extra Load |
| Section Width (mm) | 245 |
| Aspect Ratio | 45 |
| Overall Diameter (in) | 26.7 |
| Tread Depth (/32") | 9 |
| Treadwear | 540 |
| Traction Grade | A |
| Temperature Grade | A |
| UTQG | 540AA |
| Warranty | 55K |
Frequently asked questions
What kind of tire is the Michelin Primacy Tour A/S?
The Michelin Primacy Tour A/S in 245/45R18 is a all season tire.
What are the treadwear and warranty ratings on the Michelin Primacy Tour A/S?
This tire carries a treadwear grade of 540, traction grade A, temperature grade A under UTQG. The manufacturer's warranty is 55K.
What does 100H mean on the Michelin Primacy Tour A/S?
100H breaks down as load index 100 — rated for 1,764 lbs per tire — with an H speed rating, good for a maximum sustained 130 mph.
Keep shopping
Shop all 245/45R18 tires, browse Michelin tires, see every Michelin Primacy Tour A/S size, or view all tires at ThreePiece.us.
- BRAND:
- Michelin
- Model:
- Primacy Tour A/S
- Size:
- 245/45R18XL
- Aspect Ratio:
- 45
- Load Index:
- 100
- Load Range:
- Extra Load
- Section Width:
- 245
- Service Description:
- 100H
- Speed Index:
- H
- Temperature:
- A
- Tire Rim Diameter:
- 26.7
- Tire Type:
- All Season
- Traction:
- A
- Tread Wear:
- 540
- Tread Depth:
- 9
- UQTG:
- 540AA
- Warranty:
- 55K
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