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Cooper
Cooper Discoverer STT Pro 31X10.50R15/6 109Q - 170110034
Cooper Discoverer STT Pro 31X10.50R15/6 109Q - 170110034
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Looking for a 31X10.5R15 all season tire? The Cooper Discoverer STT Pro is available now at ThreePiece.us with free shipping on every order and Affirm financing at checkout.
What 31X10.5R15 means
Flotation sizes read in inches: 31X10.5R15 stands about 31 inches tall, measures about 10.5 inches wide, and mounts on a 15-inch wheel. At that nominal height it turns roughly 651 revolutions per mile. Overall diameter is the number to watch for clearance and speedometer accuracy when you size up.
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 Q corresponds to a maximum sustained speed of 99 mph.
Specifications
| Size | 31X10.50R15/6 |
| Tire Type | All Season |
| Service Description | 109Q |
| Load Index | 109 |
| Speed Rating | Q |
| Load Range | 6 |
| Section Width (mm) | 10.50 |
| Aspect Ratio | 31 |
| Overall Diameter (in) | 30.75 |
| Tread Depth (/32") | 20 |
Frequently asked questions
What kind of tire is the Cooper Discoverer STT Pro?
The Cooper Discoverer STT Pro in 31X10.5R15 is a all season tire.
Will 31X10.5R15 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 31X10.5R15, this tire matches your vehicle's fitment. If you're changing sizes, compare overall diameter to keep your speedometer and clearances right.
What does 109Q mean on the Cooper Discoverer STT Pro?
109Q breaks down as load index 109 — rated for 2,271 lbs per tire — with a Q speed rating, good for a maximum sustained 99 mph.
Keep shopping
Browse Cooper tires, see every Cooper Discoverer STT Pro size, or view all tires at ThreePiece.us.
- BRAND:
- Cooper
- Model:
- Discoverer STT Pro
- Size:
- 31X10.50R15/6
- Aspect Ratio:
- 31
- Load Index:
- 109
- Load Range:
- 6
- Section Width:
- 10.50
- Service Description:
- 109Q
- Speed Index:
- Q
- Tire Rim Diameter:
- 30.75
- Tire Type:
- All Season
- Tread Depth:
- 20
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