Write a Review
Toyo
Toyo TOY Proxes ST III 255/55R18XL
Toyo TOY Proxes ST III 255/55R18XL
📧 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 Toyo Proxes ST III 255/55R18 at ThreePiece.us — free shipping on every order, Affirm financing available, and fast delivery nationwide.
What 255/55R18 means
In the size 255/55R18, 255 is the section width in millimeters (10.04 in), 55 is the aspect ratio — the sidewall stands 55% as tall as the tire is wide, or 140.2 mm (5.52 in) — R denotes radial construction, and 18 is the wheel diameter in inches. That works out to an overall diameter of about 29.04 inches, turning roughly 694 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 manufacturer lists the overall diameter of this specific tire as 18 inches — when clearance is tight, go by the published figure rather than the nominal size math.
The service description on this tire decodes to a load index of 109 — a maximum load of 2,271 lbs per tire. The speed symbol V corresponds to a maximum sustained speed of 149 mph.
Specifications
| Size | 255/55R18xL |
| Tire Type | Highway |
| Service Description | 109V |
| Load Index | 109 |
| Speed Rating | V |
| Load Range | XL |
| Section Width (mm) | 255 |
| Aspect Ratio | 55 |
| Overall Diameter (in) | 18 |
| Tread Depth (/32") | 10.1 |
| Treadwear | 500 |
| Traction Grade | A |
| Temperature Grade | A |
| UTQG | 500AA |
| Warranty | 40K |
Frequently asked questions
What are the treadwear and warranty ratings on the Toyo Proxes ST III?
This tire carries a treadwear grade of 500, traction grade A, temperature grade A under UTQG. The manufacturer's warranty is 40K.
What does 109V mean on the Toyo Proxes ST III?
109V breaks down as load index 109 — rated for 2,271 lbs per tire — with a V speed rating, good for a maximum sustained 149 mph.
What kind of tire is the Toyo Proxes ST III?
The Toyo Proxes ST III in 255/55R18 is a highway tire.
Keep shopping
Shop all 255/55R18 tires, see every Toyo Proxes ST III size, or view all tires at ThreePiece.us.
- Brand:
- Toyo
- Model:
- TOY Proxes ST III
- Size:
- 255/55R18xL
- Aspect Ratio:
- 55
- Load Index:
- 109
- Load Range:
- XL
- Section Width:
- 255
- Service Description:
- 109V
- Speed Index:
- V
- Temperature:
- A
- Tire Rim Diameter:
- 18
- Tire Type:
- Highway
- Traction:
- A
- Tread Wear:
- 500
- Tread Depth:
- 10.1
- UQTG:
- 500AA
- Warranty:
- 40K
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