Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 315/30-30 | 38/12.5-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 37.44 (951) | 38.03 (965.92) | 0.59 (14.92) 1.6% |
| Width inches (mm) | 12.4 (315) | 12.52 (318) | 0.12 (3) 1% |
| Circum. inches (mm) | 117.62 (2987.65) | 119.47 (3034.53) | 1.85 (46.87) 1.6% |
| Sidewall Height inches (mm) | 3.72 (94.5) | 9.01 (228.96) | 5.29 (134.46) 142.3% |
| Revolutions per mile (km) | 538.66 (334.71) | 530.34 (329.54) | -8.32 (-5.17) -1.5% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.31 mph (32.69 km/h) |
| 25 mph (40.23 km/h) | 25.39 mph (40.86 km/h) |
| 30 mph (48.28 km/h) | 30.47 mph (49.04 km/h) |
| 35 mph (56.33 km/h) | 35.55 mph (57.21 km/h) |
| 40 mph (64.37 km/h) | 40.63 mph (65.38 km/h) |
| 45 mph (72.42 km/h) | 45.71 mph (73.56 km/h) |
| 50 mph (80.47 km/h) | 50.78 mph (81.73 km/h) |
| 55 mph (88.51 km/h) | 55.86 mph (89.9 km/h) |
| 60 mph (96.56 km/h) | 60.94 mph (98.08 km/h) |
| 65 mph (104.61 km/h) | 66.02 mph (106.25 km/h) |
| 70 mph (112.65 km/h) | 71.1 mph (114.42 km/h) |
| 75 mph (120.7 km/h) | 76.18 mph (122.59 km/h) |
| 80 mph (128.75 km/h) | 81.26 mph (130.77 km/h) |
| 85 mph (136.79 km/h) | 86.33 mph (138.94 km/h) |
| 90 mph (144.84 km/h) | 91.41 mph (147.11 km/h) |
| 95 mph (152.89 km/h) | 96.49 mph (155.29 km/h) |
| 100 mph (160.93 km/h) | 101.57 mph (163.46 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1350 | 1568 | 1688 | 1763 | 1844 | 1901 | 1964 | 2039 | 2142 | 2246 | 2360 | 2452 | 2619 | 2803 | 2946 | 3038 | 3090 | 3279 | 3543 | 4118 |
Better Fuel Economy Factory Ratios Increased Power
