Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 38/15.5-20 | 315/65-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 37.99 (965.04) | 36.12 (917.5) | -1.87 (-47.54) -4.9% |
| Width inches (mm) | 15.51 (394) | 12.4 (315) | -3.11 (-79) -20.1% |
| Circum. inches (mm) | 119.36 (3031.76) | 113.48 (2882.41) | -5.88 (-149.35) -4.9% |
| Sidewall Height inches (mm) | 9 (228.52) | 8.06 (204.75) | -0.94 (-23.77) -10.4% |
| Revolutions per mile (km) | 530.83 (329.84) | 558.33 (346.93) | 27.5 (17.09) 5.2% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.01 mph (30.6 km/h) |
| 25 mph (40.23 km/h) | 23.77 mph (38.25 km/h) |
| 30 mph (48.28 km/h) | 28.52 mph (45.9 km/h) |
| 35 mph (56.33 km/h) | 33.28 mph (53.55 km/h) |
| 40 mph (64.37 km/h) | 38.03 mph (61.2 km/h) |
| 45 mph (72.42 km/h) | 42.78 mph (68.85 km/h) |
| 50 mph (80.47 km/h) | 47.54 mph (76.5 km/h) |
| 55 mph (88.51 km/h) | 52.29 mph (84.15 km/h) |
| 60 mph (96.56 km/h) | 57.04 mph (91.8 km/h) |
| 65 mph (104.61 km/h) | 61.8 mph (99.45 km/h) |
| 70 mph (112.65 km/h) | 66.55 mph (107.1 km/h) |
| 75 mph (120.7 km/h) | 71.31 mph (114.76 km/h) |
| 80 mph (128.75 km/h) | 76.06 mph (122.41 km/h) |
| 85 mph (136.79 km/h) | 80.81 mph (130.06 km/h) |
| 90 mph (144.84 km/h) | 85.57 mph (137.71 km/h) |
| 95 mph (152.89 km/h) | 90.32 mph (145.36 km/h) |
| 100 mph (160.93 km/h) | 95.07 mph (153.01 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1421 | 1651 | 1778 | 1856 | 1941 | 2001 | 2068 | 2146 | 2255 | 2364 | 2485 | 2582 | 2757 | 2951 | 3102 | 3198 | 3253 | 3452 | 3730 | 4335 |
Better Fuel Economy Factory Ratios Increased Power
