Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 40/12.5-20 | 275/70-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 40.03 (1016.8) | 33.16 (842.2) | -6.87 (-174.6) -17.2% |
| Width inches (mm) | 12.52 (318) | 10.83 (275) | -1.69 (-43) -13.5% |
| Circum. inches (mm) | 125.76 (3194.37) | 104.17 (2645.85) | -21.6 (-548.52) -17.2% |
| Sidewall Height inches (mm) | 10.02 (254.4) | 7.58 (192.5) | -2.44 (-61.9) -24.3% |
| Revolutions per mile (km) | 503.81 (313.05) | 608.25 (377.95) | 104.45 (64.9) 20.7% |
275/70-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 16.57 mph (26.66 km/h) |
| 25 mph (40.23 km/h) | 20.71 mph (33.32 km/h) |
| 30 mph (48.28 km/h) | 24.85 mph (39.99 km/h) |
| 35 mph (56.33 km/h) | 28.99 mph (46.65 km/h) |
| 40 mph (64.37 km/h) | 33.13 mph (53.32 km/h) |
| 45 mph (72.42 km/h) | 37.27 mph (59.98 km/h) |
| 50 mph (80.47 km/h) | 41.41 mph (66.65 km/h) |
| 55 mph (88.51 km/h) | 45.56 mph (73.31 km/h) |
| 60 mph (96.56 km/h) | 49.7 mph (79.98 km/h) |
| 65 mph (104.61 km/h) | 53.84 mph (86.64 km/h) |
| 70 mph (112.65 km/h) | 57.98 mph (93.31 km/h) |
| 75 mph (120.7 km/h) | 62.12 mph (99.97 km/h) |
| 80 mph (128.75 km/h) | 66.26 mph (106.64 km/h) |
| 85 mph (136.79 km/h) | 70.4 mph (113.3 km/h) |
| 90 mph (144.84 km/h) | 74.55 mph (119.97 km/h) |
| 95 mph (152.89 km/h) | 78.69 mph (126.63 km/h) |
| 100 mph (160.93 km/h) | 82.83 mph (133.3 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1548 | 1798 | 1937 | 2022 | 2114 | 2180 | 2253 | 2338 | 2457 | 2575 | 2707 | 2813 | 3004 | 3214 | 3379 | 3484 | 3544 | 3761 | 4064 | 4723 |
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