Write a Review
Haida
Haida HD921 245/40R18
Haida HD921 245/40R18
📧 Get Fitment Help
Verify parts fit & get product recommendations
Lease-to-own for as low as
/week
Get Started
Guaranteed to Fit — confirm your size with the fitment checker on this page
Price Match Guarantee Learn More
Free Mount & Balance
Free Shipping
OUT OF STOCK 
📧 Get Fitment Help
Verify parts fit & get product recommendations
The Haida HD921 in 245/40R18 ships free from ThreePiece.us, with Affirm financing available at checkout and fast delivery from a nationwide warehouse network.
What 245/40R18 means
In the size 245/40R18, 245 is the section width in millimeters (9.65 in), 40 is the aspect ratio — the sidewall stands 40% as tall as the tire is wide, or 98.0 mm (3.86 in) — R denotes radial construction, and 18 is the wheel diameter in inches. That works out to an overall diameter of about 25.72 inches, turning roughly 784 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 97 — a maximum load of 1,609 lbs per tire. The speed symbol W corresponds to a maximum sustained speed of 168 mph.
Specifications
| Size | 245/40R18 |
| Service Description | 97W |
| Load Index | 97 |
| Speed Rating | W |
| Section Width (mm) | 245 |
| Aspect Ratio | 40 |
| Temperature Grade | ATIRE RIM DIAMETER=18TIRE TYPE=TRACTION=ATREAD WEAR=320TREAD DEPTH=UQTG=320 A AWARRANTY= |
Frequently asked questions
What does 97W mean on the Haida HD921?
97W breaks down as load index 97 — rated for 1,609 lbs per tire — with a W speed rating, good for a maximum sustained 168 mph.
Will 245/40R18 tires fit my vehicle?
Check the size molded into your current tire's sidewall or the tire placard inside the driver's door jamb — if it reads 245/40R18, this tire matches your vehicle's fitment. If you're changing sizes, compare overall diameter to keep your speedometer and clearances right. See every 245/40R18 tire in stock to compare options.
How fast does this tire ship?
Every order at ThreePiece.us ships free, with fast delivery from a nationwide warehouse network. Affirm financing is available at checkout.
Keep shopping
Shop all 245/40R18 tires, browse Haida tires, see every Haida HD921 size, or view all tires at ThreePiece.us.
- BRAND:
- Haida
- MODEL:
- HD921
- SIZE:
- 245/40R18
- ASPECT RATIO:
- 40
- LOAD INDEX:
- 97
- SECTION WIDTH:
- 245
- SERVICE DESCRIPTION:
- 97W
- SPEED INDEX:
- W
- TEMPERATURE:
- ATIRE RIM DIAMETER=18TIRE TYPE=TRACTION=ATREAD WEAR=320TREAD DEPTH=UQTG=320 A AWARRANTY=
PRODUCT REVIEWS (0)
Overall Rankings
Have you tried this product?
WRITE A REVIEWNo reviews for this product yet. Be the first to write a review!
Write a Review