Write a Review
Cooper
Cooper Discoverer Rugged Trek 255/70R18XL 116T - 171104005
Cooper Discoverer Rugged Trek 255/70R18XL 116T - 171104005
📧 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
Looking for a 255/70R18 all season tire? The Cooper Discoverer Rugged Trek is available now at ThreePiece.us with free shipping on every order and Affirm financing at checkout.
What 255/70R18 means
In the size 255/70R18, 255 is the section width in millimeters (10.04 in), 70 is the aspect ratio — the sidewall stands 70% as tall as the tire is wide, or 178.5 mm (7.03 in) — R denotes radial construction, and 18 is the wheel diameter in inches. That works out to an overall diameter of about 32.06 inches, turning roughly 629 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 32.44 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 116 — a maximum load of 2,756 lbs per tire. The speed symbol T corresponds to a maximum sustained speed of 118 mph.
Load Range E corresponds to a 10-ply rating.
Specifications
| Size | 255/70R18XL |
| Tire Type | All Season |
| Service Description | 116T |
| Load Index | 116 |
| Speed Rating | T |
| Load Range | Extra Load |
| Section Width (mm) | 255 |
| Aspect Ratio | 70 |
| Overall Diameter (in) | 32.44 |
| Tread Depth (/32") | 16 |
| Treadwear | 600 |
| Traction Grade | A |
| Temperature Grade | B |
| UTQG | 600AB |
| Warranty | 60K |
Frequently asked questions
What kind of tire is the Cooper Discoverer Rugged Trek?
The Cooper Discoverer Rugged Trek in 255/70R18 is a all season tire.
What are the treadwear and warranty ratings on the Cooper Discoverer Rugged Trek?
This tire carries a treadwear grade of 600, traction grade A, temperature grade B under UTQG. The manufacturer's warranty is 60K.
What does 116T mean on the Cooper Discoverer Rugged Trek?
116T breaks down as load index 116 — rated for 2,756 lbs per tire — with a T speed rating, good for a maximum sustained 118 mph.
Keep shopping
Shop all 255/70R18 tires, browse Cooper tires, see every Cooper Discoverer Rugged Trek size, or view all tires at ThreePiece.us.
- BRAND:
- Cooper
- Model:
- Discoverer Rugged Trek
- Size:
- 255/70R18XL
- Aspect Ratio:
- 70
- Load Index:
- 116
- Load Range:
- Extra Load
- Section Width:
- 255
- Service Description:
- 116T
- Speed Index:
- T
- Temperature:
- B
- Tire Rim Diameter:
- 32.44
- Tire Type:
- All Season
- Traction:
- A
- Tread Wear:
- 600
- Tread Depth:
- 16
- UQTG:
- 600AB
- Warranty:
- 60K
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