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Michelin
Michelin Primacy MXM4 225/45R18 91H - 56405
Michelin Primacy MXM4 225/45R18 91H - 56405
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Looking for a 225/45R18 all season tire? The Michelin Primacy MXM4 is available now at ThreePiece.us with free shipping on every order and Affirm financing at checkout.
What 225/45R18 means
In the size 225/45R18, 225 is the section width in millimeters (8.86 in), 45 is the aspect ratio — the sidewall stands 45% as tall as the tire is wide, or 101.2 mm (3.99 in) — R denotes radial construction, and 18 is the wheel diameter in inches. That works out to an overall diameter of about 25.97 inches, turning roughly 777 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 91 — a maximum load of 1,356 lbs per tire. The speed symbol H corresponds to a maximum sustained speed of 130 mph.
Specifications
| Size | 225/45R18 |
| Tire Type | All Season |
| Service Description | 91H |
| Load Index | 91 |
| Speed Rating | H |
| Load Range | Standard Load |
| Section Width (mm) | 225 |
| Aspect Ratio | 45 |
| Overall Diameter (in) | 25.9 |
| Tread Depth (/32") | 8.5 |
| Treadwear | 500 |
| Traction Grade | A |
| Temperature Grade | A |
| UTQG | 500AA |
| Warranty | 30K |
Frequently asked questions
What kind of tire is the Michelin Primacy MXM4?
The Michelin Primacy MXM4 in 225/45R18 is a all season tire.
What are the treadwear and warranty ratings on the Michelin Primacy MXM4?
This tire carries a treadwear grade of 500, traction grade A, temperature grade A under UTQG. The manufacturer's warranty is 30K.
What does 91H mean on the Michelin Primacy MXM4?
91H breaks down as load index 91 — rated for 1,356 lbs per tire — with an H speed rating, good for a maximum sustained 130 mph.
Keep shopping
Shop all 225/45R18 tires, browse Michelin tires, see every Michelin Primacy MXM4 size, or view all tires at ThreePiece.us.
- BRAND:
- Michelin
- Model:
- Primacy MXM4
- Size:
- 225/45R18
- Aspect Ratio:
- 45
- Load Index:
- 91
- Load Range:
- Standard Load
- Section Width:
- 225
- Service Description:
- 91H
- Speed Index:
- H
- Temperature:
- A
- Tire Rim Diameter:
- 25.9
- Tire Type:
- All Season
- Traction:
- A
- Tread Wear:
- 500
- Tread Depth:
- 8.5
- UQTG:
- 500AA
- Warranty:
- 30K
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