Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 38/13.5-20 | 37/12.5-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 38.1 (967.62) | 37.03 (940.48) | -1.07 (-27.14) -2.8% |
| Width inches (mm) | 13.5 (343) | 12.52 (318) | -0.98 (-25) -7.3% |
| Circum. inches (mm) | 119.68 (3039.87) | 116.32 (2954.61) | -3.36 (-85.26) -2.8% |
| Sidewall Height inches (mm) | 9.05 (229.81) | 8.51 (216.24) | -0.53 (-13.57) -5.9% |
| Revolutions per mile (km) | 529.41 (328.96) | 544.69 (338.45) | 15.28 (9.49) 2.9% |
37/12.5-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.44 mph (31.28 km/h) |
| 25 mph (40.23 km/h) | 24.3 mph (39.11 km/h) |
| 30 mph (48.28 km/h) | 29.16 mph (46.93 km/h) |
| 35 mph (56.33 km/h) | 34.02 mph (54.75 km/h) |
| 40 mph (64.37 km/h) | 38.88 mph (62.57 km/h) |
| 45 mph (72.42 km/h) | 43.74 mph (70.39 km/h) |
| 50 mph (80.47 km/h) | 48.6 mph (78.21 km/h) |
| 55 mph (88.51 km/h) | 53.46 mph (86.03 km/h) |
| 60 mph (96.56 km/h) | 58.32 mph (93.85 km/h) |
| 65 mph (104.61 km/h) | 63.18 mph (101.67 km/h) |
| 70 mph (112.65 km/h) | 68.04 mph (109.49 km/h) |
| 75 mph (120.7 km/h) | 72.9 mph (117.32 km/h) |
| 80 mph (128.75 km/h) | 77.76 mph (125.14 km/h) |
| 85 mph (136.79 km/h) | 82.62 mph (132.96 km/h) |
| 90 mph (144.84 km/h) | 87.48 mph (140.78 km/h) |
| 95 mph (152.89 km/h) | 92.34 mph (148.6 km/h) |
| 100 mph (160.93 km/h) | 97.2 mph (156.42 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 | 2519 | 2690 | 2878 | 3026 | 3120 | 3173 | 3368 | 3639 | 4229 |
Better Fuel Economy Factory Ratios Increased Power
