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Mastercraft
Mastercraft Courser Trail HD 315/70R17/10 121S - 175107010
Mastercraft Courser Trail HD 315/70R17/10 121S - 175107010
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The Mastercraft Courser Trail HD in 315/70R17 ships free from ThreePiece.us, with Affirm financing available at checkout and fast delivery from a nationwide warehouse network.
What 315/70R17 means
In the size 315/70R17, 315 is the section width in millimeters (12.40 in), 70 is the aspect ratio — the sidewall stands 70% as tall as the tire is wide, or 220.5 mm (8.68 in) — R denotes radial construction, and 17 is the wheel diameter in inches. That works out to an overall diameter of about 34.36 inches, turning roughly 587 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 121 — a maximum load of 3,197 lbs per tire. The speed symbol S corresponds to a maximum sustained speed of 112 mph.
Load Range E corresponds to a 10-ply rating.
Specifications
| Size | 315/70R17/10 |
| Tire Type | All Season |
| Service Description | 121S |
| Load Index | 121 |
| Speed Rating | S |
| Load Range | E |
| Section Width (mm) | 315 |
| Aspect Ratio | 70 |
| Overall Diameter (in) | 34.33 |
| Tread Depth (/32") | 17 |
| Warranty | 55K |
Frequently asked questions
What does 121S mean on the Mastercraft Courser Trail HD?
121S breaks down as load index 121 — rated for 3,197 lbs per tire — with an S speed rating, good for a maximum sustained 112 mph.
What kind of tire is the Mastercraft Courser Trail HD?
The Mastercraft Courser Trail HD in 315/70R17 is a all season tire.
What warranty does the Mastercraft Courser Trail HD carry?
The manufacturer's warranty on this tire is 55K.
Keep shopping
Shop all 315/70R17 tires, browse Mastercraft tires, see every Mastercraft Courser Trail HD size, or view all tires at ThreePiece.us.
- BRAND:
- Mastercraft
- Model:
- Courser Trail HD
- Size:
- 315/70R17/10
- Aspect Ratio:
- 70
- Load Index:
- 121
- Load Range:
- E
- Section Width:
- 315
- Service Description:
- 121S
- Speed Index:
- S
- Tire Rim Diameter:
- 34.33
- Tire Type:
- All Season
- Tread Depth:
- 17
- Warranty:
- 55K
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