Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 305/70-18 | 37/12.5-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 34.81 (884.2) | 37.03 (940.56) | 2.22 (56.36) 6.4% |
| Width inches (mm) | 12.01 (305) | 12.52 (318) | 0.51 (13) 4.3% |
| Circum. inches (mm) | 109.36 (2777.8) | 116.33 (2954.86) | 6.97 (177.06) 6.4% |
| Sidewall Height inches (mm) | 8.41 (213.5) | 9.51 (241.68) | 1.11 (28.18) 13.2% |
| Revolutions per mile (km) | 579.36 (360) | 544.64 (338.43) | -34.72 (-21.57) -6% |
37/12.5-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.27 mph (34.24 km/h) |
| 25 mph (40.23 km/h) | 26.59 mph (42.8 km/h) |
| 30 mph (48.28 km/h) | 31.91 mph (51.36 km/h) |
| 35 mph (56.33 km/h) | 37.23 mph (59.92 km/h) |
| 40 mph (64.37 km/h) | 42.55 mph (68.48 km/h) |
| 45 mph (72.42 km/h) | 47.87 mph (77.04 km/h) |
| 50 mph (80.47 km/h) | 53.19 mph (85.6 km/h) |
| 55 mph (88.51 km/h) | 58.51 mph (94.16 km/h) |
| 60 mph (96.56 km/h) | 63.82 mph (102.72 km/h) |
| 65 mph (104.61 km/h) | 69.14 mph (111.28 km/h) |
| 70 mph (112.65 km/h) | 74.46 mph (119.84 km/h) |
| 75 mph (120.7 km/h) | 79.78 mph (128.39 km/h) |
| 80 mph (128.75 km/h) | 85.1 mph (136.95 km/h) |
| 85 mph (136.79 km/h) | 90.42 mph (145.51 km/h) |
| 90 mph (144.84 km/h) | 95.74 mph (154.07 km/h) |
| 95 mph (152.89 km/h) | 101.06 mph (162.63 km/h) |
| 100 mph (160.93 km/h) | 106.37 mph (171.19 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1386 | 1610 | 1734 | 1811 | 1893 | 1952 | 2017 | 2094 | 2200 | 2306 | 2424 | 2518 | 2689 | 2878 | 3026 | 3120 | 3173 | 3368 | 3639 | 4229 |
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