Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 285/65-20 | 285/70-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 34.59 (878.5) | 33.71 (856.2) | -0.88 (-22.3) -2.5% |
| Width inches (mm) | 11.22 (285) | 11.22 (285) | 0 (0) 0% |
| Circum. inches (mm) | 108.66 (2759.89) | 105.9 (2689.83) | -2.76 (-70.06) -2.5% |
| Sidewall Height inches (mm) | 7.29 (185.25) | 7.85 (199.5) | 0.56 (14.25) 7.7% |
| Revolutions per mile (km) | 583.12 (362.33) | 598.31 (371.77) | 15.19 (9.44) 2.6% |
285/70-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.49 mph (31.37 km/h) |
| 25 mph (40.23 km/h) | 24.37 mph (39.21 km/h) |
| 30 mph (48.28 km/h) | 29.24 mph (47.05 km/h) |
| 35 mph (56.33 km/h) | 34.11 mph (54.9 km/h) |
| 40 mph (64.37 km/h) | 38.98 mph (62.74 km/h) |
| 45 mph (72.42 km/h) | 43.86 mph (70.58 km/h) |
| 50 mph (80.47 km/h) | 48.73 mph (78.42 km/h) |
| 55 mph (88.51 km/h) | 53.6 mph (86.27 km/h) |
| 60 mph (96.56 km/h) | 58.48 mph (94.11 km/h) |
| 65 mph (104.61 km/h) | 63.35 mph (101.95 km/h) |
| 70 mph (112.65 km/h) | 68.22 mph (109.79 km/h) |
| 75 mph (120.7 km/h) | 73.1 mph (117.64 km/h) |
| 80 mph (128.75 km/h) | 77.97 mph (125.48 km/h) |
| 85 mph (136.79 km/h) | 82.84 mph (133.32 km/h) |
| 90 mph (144.84 km/h) | 87.72 mph (141.16 km/h) |
| 95 mph (152.89 km/h) | 92.59 mph (149.01 km/h) |
| 100 mph (160.93 km/h) | 97.46 mph (156.85 km/h) |
| 2.35 | 2.73 | 2.94 | 3.07 | 3.21 | 3.31 | 3.42 | 3.55 | 3.73 | 3.91 | 4.11 | 4.27 | 4.56 | 4.88 | 5.13 | 5.29 | 5.38 | 5.71 | 6.17 | 7.17 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1523 | 1769 | 1905 | 1989 | 2080 | 2145 | 2216 | 2300 | 2417 | 2533 | 2663 | 2767 | 2954 | 3162 | 3324 | 3427 | 3486 | 3700 | 3998 | 4645 |
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