Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 285/45-21 | 285/65-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 31.1 (789.9) | 35.59 (903.9) | 4.49 (114) 14.4% |
| Width inches (mm) | 11.22 (285) | 11.22 (285) | 0 (0) 0% |
| Circum. inches (mm) | 97.7 (2481.54) | 111.8 (2839.69) | 14.1 (358.14) 14.4% |
| Sidewall Height inches (mm) | 5.05 (128.25) | 7.29 (185.25) | 2.24 (57) 44.4% |
| Revolutions per mile (km) | 648.53 (402.97) | 566.73 (352.15) | -81.79 (-50.82) -12.6% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 22.89 mph (36.83 km/h) |
| 25 mph (40.23 km/h) | 28.61 mph (46.04 km/h) |
| 30 mph (48.28 km/h) | 34.33 mph (55.25 km/h) |
| 35 mph (56.33 km/h) | 40.05 mph (64.46 km/h) |
| 40 mph (64.37 km/h) | 45.77 mph (73.66 km/h) |
| 45 mph (72.42 km/h) | 51.49 mph (82.87 km/h) |
| 50 mph (80.47 km/h) | 57.22 mph (92.08 km/h) |
| 55 mph (88.51 km/h) | 62.94 mph (101.29 km/h) |
| 60 mph (96.56 km/h) | 68.66 mph (110.5 km/h) |
| 65 mph (104.61 km/h) | 74.38 mph (119.7 km/h) |
| 70 mph (112.65 km/h) | 80.1 mph (128.91 km/h) |
| 75 mph (120.7 km/h) | 85.82 mph (138.12 km/h) |
| 80 mph (128.75 km/h) | 91.55 mph (147.33 km/h) |
| 85 mph (136.79 km/h) | 97.27 mph (156.54 km/h) |
| 90 mph (144.84 km/h) | 102.99 mph (165.75 km/h) |
| 95 mph (152.89 km/h) | 108.71 mph (174.95 km/h) |
| 100 mph (160.93 km/h) | 114.43 mph (184.16 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1442 | 1675 | 1804 | 1884 | 1970 | 2031 | 2099 | 2179 | 2289 | 2400 | 2522 | 2621 | 2799 | 2995 | 3148 | 3247 | 3302 | 3504 | 3787 | 4400 |
Better Fuel Economy Factory Ratios Increased Power
