Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 285/40-20 | 285/45-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.98 (736) | 30.1 (764.5) | 1.12 (28.5) 3.9% |
| Width inches (mm) | 11.22 (285) | 11.22 (285) | 0 (0) 0% |
| Circum. inches (mm) | 91.03 (2312.21) | 94.56 (2401.75) | 3.53 (89.54) 3.9% |
| Sidewall Height inches (mm) | 4.49 (114) | 5.05 (128.25) | 0.56 (14.25) 12.5% |
| Revolutions per mile (km) | 696.02 (432.49) | 670.07 (416.36) | -25.95 (-16.12) -3.7% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.77 mph (33.43 km/h) |
| 25 mph (40.23 km/h) | 25.97 mph (41.79 km/h) |
| 30 mph (48.28 km/h) | 31.16 mph (50.15 km/h) |
| 35 mph (56.33 km/h) | 36.36 mph (58.51 km/h) |
| 40 mph (64.37 km/h) | 41.55 mph (66.87 km/h) |
| 45 mph (72.42 km/h) | 46.74 mph (75.22 km/h) |
| 50 mph (80.47 km/h) | 51.94 mph (83.58 km/h) |
| 55 mph (88.51 km/h) | 57.13 mph (91.94 km/h) |
| 60 mph (96.56 km/h) | 62.32 mph (100.3 km/h) |
| 65 mph (104.61 km/h) | 67.52 mph (108.66 km/h) |
| 70 mph (112.65 km/h) | 72.71 mph (117.02 km/h) |
| 75 mph (120.7 km/h) | 77.9 mph (125.37 km/h) |
| 80 mph (128.75 km/h) | 83.1 mph (133.73 km/h) |
| 85 mph (136.79 km/h) | 88.29 mph (142.09 km/h) |
| 90 mph (144.84 km/h) | 93.49 mph (150.45 km/h) |
| 95 mph (152.89 km/h) | 98.68 mph (158.81 km/h) |
| 100 mph (160.93 km/h) | 103.87 mph (167.17 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1705 | 1981 | 2133 | 2228 | 2329 | 2402 | 2482 | 2576 | 2707 | 2837 | 2982 | 3098 | 3309 | 3541 | 3722 | 3839 | 3904 | 4143 | 4477 | 5203 |
Better Fuel Economy Factory Ratios Increased Power
