Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 37/12.5-18 | 325/65-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 37.03 (940.56) | 34.63 (879.7) | -2.4 (-60.86) -6.5% |
| Width inches (mm) | 12.52 (318) | 12.8 (325) | 0.28 (7) 2.2% |
| Circum. inches (mm) | 116.33 (2954.86) | 108.81 (2763.66) | -7.53 (-191.2) -6.5% |
| Sidewall Height inches (mm) | 9.51 (241.68) | 8.32 (211.25) | -1.2 (-30.43) -12.6% |
| Revolutions per mile (km) | 544.64 (338.43) | 582.32 (361.84) | 37.68 (23.41) 6.9% |
325/65-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 18.71 mph (30.1 km/h) |
| 25 mph (40.23 km/h) | 23.38 mph (37.63 km/h) |
| 30 mph (48.28 km/h) | 28.06 mph (45.16 km/h) |
| 35 mph (56.33 km/h) | 32.74 mph (52.68 km/h) |
| 40 mph (64.37 km/h) | 37.41 mph (60.21 km/h) |
| 45 mph (72.42 km/h) | 42.09 mph (67.73 km/h) |
| 50 mph (80.47 km/h) | 46.76 mph (75.26 km/h) |
| 55 mph (88.51 km/h) | 51.44 mph (82.79 km/h) |
| 60 mph (96.56 km/h) | 56.12 mph (90.31 km/h) |
| 65 mph (104.61 km/h) | 60.79 mph (97.84 km/h) |
| 70 mph (112.65 km/h) | 65.47 mph (105.36 km/h) |
| 75 mph (120.7 km/h) | 70.15 mph (112.89 km/h) |
| 80 mph (128.75 km/h) | 74.82 mph (120.42 km/h) |
| 85 mph (136.79 km/h) | 79.5 mph (127.94 km/h) |
| 90 mph (144.84 km/h) | 84.18 mph (135.47 km/h) |
| 95 mph (152.89 km/h) | 88.85 mph (143 km/h) |
| 100 mph (160.93 km/h) | 93.53 mph (150.52 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1482 | 1722 | 1854 | 1936 | 2024 | 2087 | 2157 | 2239 | 2352 | 2466 | 2592 | 2693 | 2876 | 3077 | 3235 | 3336 | 3393 | 3601 | 3891 | 4521 |
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