Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 365/80-20 | 40/15.5-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 42.99 (1092) | 40.17 (1020.2) | -2.83 (-71.8) -6.6% |
| Width inches (mm) | 14.37 (365) | 15.51 (394) | 1.14 (29) 7.9% |
| Circum. inches (mm) | 135.06 (3430.62) | 126.18 (3205.05) | -8.88 (-225.57) -6.6% |
| Sidewall Height inches (mm) | 11.5 (292) | 10.08 (256.1) | -1.41 (-35.9) -12.3% |
| Revolutions per mile (km) | 469.11 (291.49) | 502.13 (312.01) | 33.02 (20.51) 7% |
40/15.5-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 18.68 mph (30.07 km/h) |
| 25 mph (40.23 km/h) | 23.36 mph (37.59 km/h) |
| 30 mph (48.28 km/h) | 28.03 mph (45.11 km/h) |
| 35 mph (56.33 km/h) | 32.7 mph (52.62 km/h) |
| 40 mph (64.37 km/h) | 37.37 mph (60.14 km/h) |
| 45 mph (72.42 km/h) | 42.04 mph (67.66 km/h) |
| 50 mph (80.47 km/h) | 46.71 mph (75.18 km/h) |
| 55 mph (88.51 km/h) | 51.38 mph (82.69 km/h) |
| 60 mph (96.56 km/h) | 56.05 mph (90.21 km/h) |
| 65 mph (104.61 km/h) | 60.73 mph (97.73 km/h) |
| 70 mph (112.65 km/h) | 65.4 mph (105.25 km/h) |
| 75 mph (120.7 km/h) | 70.07 mph (112.76 km/h) |
| 80 mph (128.75 km/h) | 74.74 mph (120.28 km/h) |
| 85 mph (136.79 km/h) | 79.41 mph (127.8 km/h) |
| 90 mph (144.84 km/h) | 84.08 mph (135.32 km/h) |
| 95 mph (152.89 km/h) | 88.75 mph (142.84 km/h) |
| 100 mph (160.93 km/h) | 93.42 mph (150.35 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1278 | 1484 | 1599 | 1669 | 1745 | 1800 | 1860 | 1930 | 2028 | 2126 | 2235 | 2322 | 2480 | 2654 | 2789 | 2876 | 2925 | 3105 | 3355 | 3899 |
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