Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 295/30-21 | 285/30-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 27.97 (710.4) | 26.73 (679) | -1.24 (-31.4) -4.4% |
| Width inches (mm) | 11.61 (295) | 11.22 (285) | -0.39 (-10) -3.4% |
| Circum. inches (mm) | 87.87 (2231.79) | 83.98 (2133.14) | -3.88 (-98.65) -4.4% |
| Sidewall Height inches (mm) | 3.48 (88.5) | 3.37 (85.5) | -0.12 (-3) -3.4% |
| Revolutions per mile (km) | 721.1 (448.07) | 754.45 (468.79) | 33.35 (20.72) 4.6% |
285/30-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.12 mph (30.76 km/h) |
| 25 mph (40.23 km/h) | 23.89 mph (38.46 km/h) |
| 30 mph (48.28 km/h) | 28.67 mph (46.15 km/h) |
| 35 mph (56.33 km/h) | 33.45 mph (53.84 km/h) |
| 40 mph (64.37 km/h) | 38.23 mph (61.53 km/h) |
| 45 mph (72.42 km/h) | 43.01 mph (69.22 km/h) |
| 50 mph (80.47 km/h) | 47.79 mph (76.91 km/h) |
| 55 mph (88.51 km/h) | 52.57 mph (84.6 km/h) |
| 60 mph (96.56 km/h) | 57.35 mph (92.29 km/h) |
| 65 mph (104.61 km/h) | 62.13 mph (99.98 km/h) |
| 70 mph (112.65 km/h) | 66.91 mph (107.67 km/h) |
| 75 mph (120.7 km/h) | 71.68 mph (115.37 km/h) |
| 80 mph (128.75 km/h) | 76.46 mph (123.06 km/h) |
| 85 mph (136.79 km/h) | 81.24 mph (130.75 km/h) |
| 90 mph (144.84 km/h) | 86.02 mph (138.44 km/h) |
| 95 mph (152.89 km/h) | 90.8 mph (146.13 km/h) |
| 100 mph (160.93 km/h) | 95.58 mph (153.82 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1920 | 2230 | 2402 | 2508 | 2623 | 2704 | 2794 | 2900 | 3047 | 3194 | 3358 | 3489 | 3725 | 3987 | 4191 | 4322 | 4395 | 4665 | 5041 | 5858 |
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