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Michelin
Michelin Pilot Sport 4 S 305/25ZR21XL 98(Y) - 21039
Michelin Pilot Sport 4 S 305/25ZR21XL 98(Y) - 21039
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Shop the Michelin Pilot Sport 4 S 305/25R21 at ThreePiece.us — free shipping on every order, Affirm financing available, and fast delivery nationwide.
What 305/25R21 means
In the size 305/25R21, 305 is the section width in millimeters (12.01 in), 25 is the aspect ratio — the sidewall stands 25% as tall as the tire is wide, or 76.2 mm (3.00 in) — R denotes radial construction, and 21 is the wheel diameter in inches. That works out to an overall diameter of about 27.00 inches, turning roughly 747 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 98 — a maximum load of 1,653 lbs per tire. The speed symbol Y corresponds to a maximum sustained speed of 186 mph.
Load Range E corresponds to a 10-ply rating.
Specifications
| Size | 305/25ZR21XL |
| Tire Type | Summer |
| Service Description | 98Y |
| Load Index | 98 |
| Speed Rating | Y |
| Load Range | Extra Load |
| Section Width (mm) | 305 |
| Aspect Ratio | 25 |
| Overall Diameter (in) | 27 |
| Tread Depth (/32") | 9.5 |
| Treadwear | 300 |
| Traction Grade | AA |
| Temperature Grade | A |
| UTQG | 300AAA |
| Warranty | 30K |
Frequently asked questions
What are the treadwear and warranty ratings on the Michelin Pilot Sport 4 S?
This tire carries a treadwear grade of 300, traction grade AA, temperature grade A under UTQG. The manufacturer's warranty is 30K.
What does 98Y mean on the Michelin Pilot Sport 4 S?
98Y breaks down as load index 98 — rated for 1,653 lbs per tire — with a Y speed rating, good for a maximum sustained 186 mph.
What kind of tire is the Michelin Pilot Sport 4 S?
The Michelin Pilot Sport 4 S in 305/25R21 is a summer tire.
Keep shopping
Browse Michelin tires, see every Michelin Pilot Sport 4 S size, or view all tires at ThreePiece.us.
- BRAND:
- Michelin
- Model:
- Pilot Sport 4 S
- Size:
- 305/25ZR21XL
- Aspect Ratio:
- 25
- Load Index:
- 98
- Load Range:
- Extra Load
- Section Width:
- 305
- Service Description:
- 98Y
- Speed Index:
- Y
- Temperature:
- A
- Tire Rim Diameter:
- 27
- Tire Type:
- Summer
- Traction:
- AA
- Tread Wear:
- 300
- Tread Depth:
- 9.5
- UQTG:
- 300AAA
- Warranty:
- 30K
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