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Continental
Continental CON ExtremeContact Sport 255/40ZR18XL
Continental CON ExtremeContact Sport 255/40ZR18XL
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Looking for a 255/40R18 high performance tire? The Continental ExtremeContact Sport is available now at ThreePiece.us with free shipping on every order and Affirm financing at checkout.
What 255/40R18 means
In the size 255/40R18, 255 is the section width in millimeters (10.04 in), 40 is the aspect ratio — the sidewall stands 40% as tall as the tire is wide, or 102.0 mm (4.02 in) — R denotes radial construction, and 18 is the wheel diameter in inches. That works out to an overall diameter of about 26.03 inches, turning roughly 775 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 99 — a maximum load of 1,709 lbs per tire. The speed symbol Y corresponds to a maximum sustained speed of 186 mph.
Specifications
| Size | 255/40ZR18XL |
| Tire Type | High Performance |
| Service Description | 99Y |
| Load Index | 99 |
| Speed Rating | Y |
| Load Range | XL |
| Section Width (mm) | 255 |
| Aspect Ratio | 40 |
| Overall Diameter (in) | 26 |
| Tread Depth (/32") | 10 |
| Treadwear | 340 |
| Traction Grade | AA |
| Temperature Grade | A |
| UTQG | 340AAA |
| Warranty | 30K |
Frequently asked questions
What kind of tire is the Continental ExtremeContact Sport?
The Continental ExtremeContact Sport in 255/40R18 is a high performance tire.
What are the treadwear and warranty ratings on the Continental ExtremeContact Sport?
This tire carries a treadwear grade of 340, traction grade AA, temperature grade A under UTQG. The manufacturer's warranty is 30K.
What does 99Y mean on the Continental ExtremeContact Sport?
99Y breaks down as load index 99 — rated for 1,709 lbs per tire — with a Y speed rating, good for a maximum sustained 186 mph.
Keep shopping
Shop all 255/40R18 tires, see every Continental ExtremeContact Sport size, or view all tires at ThreePiece.us.
- Brand:
- Continental
- Model:
- CON ExtremeContact Sport
- Size:
- 255/40ZR18XL
- Aspect Ratio:
- 40
- Load Index:
- 99
- Load Range:
- XL
- Section Width:
- 255
- Service Description:
- 99Y
- Speed Index:
- Y
- Temperature:
- A
- Tire Rim Diameter:
- 26
- Tire Type:
- High Performance
- Traction:
- AA
- Tread Wear:
- 340
- Tread Depth:
- 10
- UQTG:
- 340AAA
- Warranty:
- 30K
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