Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 38/15.5-20 | 38/12.5-17 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 37.99 (965.04) | 38.03 (966.04) | 0.04 (1) 0.1% |
| Width inches (mm) | 15.51 (394) | 12.52 (318) | -2.99 (-76) -19.3% |
| Circum. inches (mm) | 119.36 (3031.76) | 119.48 (3034.9) | 0.12 (3.14) 0.1% |
| Sidewall Height inches (mm) | 9 (228.52) | 10.52 (267.12) | 1.52 (38.6) 16.9% |
| Revolutions per mile (km) | 530.83 (329.84) | 530.28 (329.5) | -0.55 (-0.34) -0.1% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.02 mph (32.22 km/h) |
| 25 mph (40.23 km/h) | 25.03 mph (40.28 km/h) |
| 30 mph (48.28 km/h) | 30.03 mph (48.33 km/h) |
| 35 mph (56.33 km/h) | 35.04 mph (56.39 km/h) |
| 40 mph (64.37 km/h) | 40.04 mph (64.44 km/h) |
| 45 mph (72.42 km/h) | 45.05 mph (72.5 km/h) |
| 50 mph (80.47 km/h) | 50.05 mph (80.55 km/h) |
| 55 mph (88.51 km/h) | 55.06 mph (88.61 km/h) |
| 60 mph (96.56 km/h) | 60.06 mph (96.66 km/h) |
| 65 mph (104.61 km/h) | 65.07 mph (104.72 km/h) |
| 70 mph (112.65 km/h) | 70.07 mph (112.77 km/h) |
| 75 mph (120.7 km/h) | 75.08 mph (120.83 km/h) |
| 80 mph (128.75 km/h) | 80.08 mph (128.88 km/h) |
| 85 mph (136.79 km/h) | 85.09 mph (136.94 km/h) |
| 90 mph (144.84 km/h) | 90.09 mph (144.99 km/h) |
| 95 mph (152.89 km/h) | 95.1 mph (153.05 km/h) |
| 100 mph (160.93 km/h) | 100.1 mph (161.1 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1349 | 1568 | 1688 | 1763 | 1843 | 1901 | 1964 | 2039 | 2142 | 2245 | 2360 | 2452 | 2619 | 2802 | 2946 | 3038 | 3089 | 3279 | 3543 | 4117 |
Better Fuel Economy Factory Ratios Increased Power
