Write a Review
Michelin
Michelin Primacy 3 245/45R18XL 100Y - 29301
Michelin Primacy 3 245/45R18XL 100Y - 29301
📧 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
Shop the Michelin Primacy 3 245/45R18 at ThreePiece.us — free shipping on every order, Affirm financing available, and fast delivery nationwide.
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 Y corresponds to a maximum sustained speed of 186 mph.
Load Range E corresponds to a 10-ply rating.
Specifications
| Size | 245/45R18XL |
| Tire Type | Summer |
| Service Description | 100Y |
| Load Index | 100 |
| Speed Rating | Y |
| Load Range | Extra Load |
| Section Width (mm) | 245 |
| Aspect Ratio | 45 |
| Overall Diameter (in) | 26.65 |
| Tread Depth (/32") | 9 |
| Treadwear | 240 |
| Traction Grade | A |
| Temperature Grade | A |
| UTQG | 240AA |
| Warranty | 30K |
Frequently asked questions
What are the treadwear and warranty ratings on the Michelin Primacy 3?
This tire carries a treadwear grade of 240, traction grade A, temperature grade A under UTQG. The manufacturer's warranty is 30K.
What does 100Y mean on the Michelin Primacy 3?
100Y breaks down as load index 100 — rated for 1,764 lbs per tire — with a Y speed rating, good for a maximum sustained 186 mph.
What kind of tire is the Michelin Primacy 3?
The Michelin Primacy 3 in 245/45R18 is a summer tire.
Keep shopping
Shop all 245/45R18 tires, browse Michelin tires, see every Michelin Primacy 3 size, or view all tires at ThreePiece.us.
- BRAND:
- Michelin
- Model:
- Primacy 3
- Size:
- 245/45R18XL
- Aspect Ratio:
- 45
- Load Index:
- 100
- Load Range:
- Extra Load
- Section Width:
- 245
- Service Description:
- 100Y
- Speed Index:
- Y
- Temperature:
- A
- Tire Rim Diameter:
- 26.65
- Tire Type:
- Summer
- Traction:
- A
- Tread Wear:
- 240
- Tread Depth:
- 9
- UQTG:
- 240AA
- Warranty:
- 30K
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