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Grit Master
Grit Master M/T- Mud terrian 285/55R20
Grit Master M/T- Mud terrian 285/55R20
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Shop the Grit Master M/T- Mud terrian 285/55R20 at ThreePiece.us — free shipping on every order, Affirm financing available, and fast delivery nationwide.
What 285/55R20 means
In the size 285/55R20, 285 is the section width in millimeters (11.22 in), 55 is the aspect ratio — the sidewall stands 55% as tall as the tire is wide, or 156.8 mm (6.17 in) — R denotes radial construction, and 20 is the wheel diameter in inches. That works out to an overall diameter of about 32.34 inches, turning roughly 624 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 20 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 122 — a maximum load of 3,307 lbs per tire, or 119 (2,998 lbs) per tire when mounted as duals. The speed symbol Q corresponds to a maximum sustained speed of 99 mph.
Specifications
| Size | 285/55R20 |
| Service Description | 122/119Q |
| Load Index | 122/119 |
| Speed Rating | Q |
| Section Width (mm) | 285 |
| Aspect Ratio | 55 |
| Overall Diameter (in) | 20 |
Frequently asked questions
How fast does this tire ship?
Every order at ThreePiece.us ships free, with fast delivery from a nationwide warehouse network. Affirm financing is available at checkout.
What does 122/119Q mean on the Grit Master M/T- Mud terrian?
122/119Q breaks down as load index 122 — rated for 3,307 lbs per tire (119, or 2,998 lbs, in dual fitment) — with a Q speed rating, good for a maximum sustained 99 mph.
Will 285/55R20 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 285/55R20, this tire matches your vehicle's fitment. If you're changing sizes, compare overall diameter to keep your speedometer and clearances right. See every 285/55R20 tire in stock to compare options.
Keep shopping
Shop all 285/55R20 tires, browse Grit Master tires, see every Grit Master M/T- Mud terrian size, or view all tires at ThreePiece.us.
- BRAND:
- Grit Master
- Model:
- M/T- Mud terrian
- Size:
- 285/55R20
- Aspect Ratio:
- 55
- Load Index:
- 122/119
- Section Width:
- 285
- Service Description:
- 122/119Q
- Speed Index:
- Q
- Tire Rim Diameter:
- 20
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