Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 365/80-20 | 40/12.5-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 42.99 (1092) | 40.03 (1016.8) | -2.96 (-75.2) -6.9% |
| Width inches (mm) | 14.37 (365) | 12.52 (318) | -1.85 (-47) -12.9% |
| Circum. inches (mm) | 135.06 (3430.62) | 125.76 (3194.37) | -9.3 (-236.25) -6.9% |
| Sidewall Height inches (mm) | 11.5 (292) | 10.02 (254.4) | -1.48 (-37.6) -12.9% |
| Revolutions per mile (km) | 469.11 (291.49) | 503.81 (313.05) | 34.69 (21.56) 7.4% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 18.62 mph (29.97 km/h) |
| 25 mph (40.23 km/h) | 23.28 mph (37.46 km/h) |
| 30 mph (48.28 km/h) | 27.93 mph (44.96 km/h) |
| 35 mph (56.33 km/h) | 32.59 mph (52.45 km/h) |
| 40 mph (64.37 km/h) | 37.25 mph (59.94 km/h) |
| 45 mph (72.42 km/h) | 41.9 mph (67.43 km/h) |
| 50 mph (80.47 km/h) | 46.56 mph (74.93 km/h) |
| 55 mph (88.51 km/h) | 51.21 mph (82.42 km/h) |
| 60 mph (96.56 km/h) | 55.87 mph (89.91 km/h) |
| 65 mph (104.61 km/h) | 60.52 mph (97.4 km/h) |
| 70 mph (112.65 km/h) | 65.18 mph (104.9 km/h) |
| 75 mph (120.7 km/h) | 69.84 mph (112.39 km/h) |
| 80 mph (128.75 km/h) | 74.49 mph (119.88 km/h) |
| 85 mph (136.79 km/h) | 79.15 mph (127.37 km/h) |
| 90 mph (144.84 km/h) | 83.8 mph (134.87 km/h) |
| 95 mph (152.89 km/h) | 88.46 mph (142.36 km/h) |
| 100 mph (160.93 km/h) | 93.11 mph (149.85 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1282 | 1489 | 1604 | 1675 | 1751 | 1806 | 1866 | 1937 | 2035 | 2133 | 2242 | 2330 | 2488 | 2662 | 2799 | 2886 | 2935 | 3115 | 3366 | 3912 |
Better Fuel Economy Factory Ratios Increased Power
