Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 285/45-21 | 275/50-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 31.1 (789.9) | 30.83 (783) | -0.27 (-6.9) -0.9% |
| Width inches (mm) | 11.22 (285) | 10.83 (275) | -0.39 (-10) -3.5% |
| Circum. inches (mm) | 97.7 (2481.54) | 96.85 (2459.87) | -0.85 (-21.68) -0.9% |
| 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) | 654.24 (406.53) | 5.71 (3.55) 0.9% |
275/50-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.83 mph (31.91 km/h) |
| 25 mph (40.23 km/h) | 24.78 mph (39.88 km/h) |
| 30 mph (48.28 km/h) | 29.74 mph (47.86 km/h) |
| 35 mph (56.33 km/h) | 34.69 mph (55.84 km/h) |
| 40 mph (64.37 km/h) | 39.65 mph (63.81 km/h) |
| 45 mph (72.42 km/h) | 44.61 mph (71.79 km/h) |
| 50 mph (80.47 km/h) | 49.56 mph (79.76 km/h) |
| 55 mph (88.51 km/h) | 54.52 mph (87.74 km/h) |
| 60 mph (96.56 km/h) | 59.48 mph (95.72 km/h) |
| 65 mph (104.61 km/h) | 64.43 mph (103.69 km/h) |
| 70 mph (112.65 km/h) | 69.39 mph (111.67 km/h) |
| 75 mph (120.7 km/h) | 74.34 mph (119.65 km/h) |
| 80 mph (128.75 km/h) | 79.3 mph (127.62 km/h) |
| 85 mph (136.79 km/h) | 84.26 mph (135.6 km/h) |
| 90 mph (144.84 km/h) | 89.21 mph (143.58 km/h) |
| 95 mph (152.89 km/h) | 94.17 mph (151.55 km/h) |
| 100 mph (160.93 km/h) | 99.13 mph (159.53 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1665 | 1934 | 2083 | 2175 | 2274 | 2345 | 2423 | 2515 | 2643 | 2770 | 2912 | 3025 | 3231 | 3457 | 3634 | 3748 | 3812 | 4045 | 4371 | 5080 |
Better Fuel Economy Factory Ratios Increased Power
