Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 285/45-21 | 275/50-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 31.1 (789.9) | 31.83 (808.4) | 0.73 (18.5) 2.3% |
| Width inches (mm) | 11.22 (285) | 10.83 (275) | -0.39 (-10) -3.5% |
| Circum. inches (mm) | 97.7 (2481.54) | 99.99 (2539.66) | 2.29 (58.12) 2.3% |
| Sidewall Height inches (mm) | 5.05 (128.25) | 5.41 (137.5) | 0.36 (9.25) 7.2% |
| Revolutions per mile (km) | 648.53 (402.97) | 633.68 (393.75) | -14.84 (-9.22) -2.3% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.47 mph (32.94 km/h) |
| 25 mph (40.23 km/h) | 25.59 mph (41.18 km/h) |
| 30 mph (48.28 km/h) | 30.7 mph (49.41 km/h) |
| 35 mph (56.33 km/h) | 35.82 mph (57.65 km/h) |
| 40 mph (64.37 km/h) | 40.94 mph (65.88 km/h) |
| 45 mph (72.42 km/h) | 46.05 mph (74.12 km/h) |
| 50 mph (80.47 km/h) | 51.17 mph (82.35 km/h) |
| 55 mph (88.51 km/h) | 56.29 mph (90.59 km/h) |
| 60 mph (96.56 km/h) | 61.41 mph (98.82 km/h) |
| 65 mph (104.61 km/h) | 66.52 mph (107.06 km/h) |
| 70 mph (112.65 km/h) | 71.64 mph (115.29 km/h) |
| 75 mph (120.7 km/h) | 76.76 mph (123.53 km/h) |
| 80 mph (128.75 km/h) | 81.87 mph (131.76 km/h) |
| 85 mph (136.79 km/h) | 86.99 mph (140 km/h) |
| 90 mph (144.84 km/h) | 92.11 mph (148.23 km/h) |
| 95 mph (152.89 km/h) | 97.22 mph (156.47 km/h) |
| 100 mph (160.93 km/h) | 102.34 mph (164.7 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1613 | 1873 | 2017 | 2107 | 2203 | 2271 | 2347 | 2436 | 2560 | 2683 | 2820 | 2930 | 3129 | 3349 | 3520 | 3630 | 3692 | 3918 | 4234 | 4920 |
Better Fuel Economy Factory Ratios Increased Power
