Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 38/15.5-20 | 305/70-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 37.99 (965.04) | 36.81 (935) | -1.18 (-30.04) -3.1% |
| Width inches (mm) | 15.51 (394) | 12.01 (305) | -3.5 (-89) -22.6% |
| Circum. inches (mm) | 119.36 (3031.76) | 115.65 (2937.39) | -3.72 (-94.37) -3.1% |
| Sidewall Height inches (mm) | 9 (228.52) | 8.41 (213.5) | -0.59 (-15.02) -6.6% |
| Revolutions per mile (km) | 530.83 (329.84) | 547.88 (340.44) | 17.05 (10.6) 3.2% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.38 mph (31.19 km/h) |
| 25 mph (40.23 km/h) | 24.22 mph (38.98 km/h) |
| 30 mph (48.28 km/h) | 29.07 mph (46.78 km/h) |
| 35 mph (56.33 km/h) | 33.91 mph (54.57 km/h) |
| 40 mph (64.37 km/h) | 38.75 mph (62.37 km/h) |
| 45 mph (72.42 km/h) | 43.6 mph (70.17 km/h) |
| 50 mph (80.47 km/h) | 48.44 mph (77.96 km/h) |
| 55 mph (88.51 km/h) | 53.29 mph (85.76 km/h) |
| 60 mph (96.56 km/h) | 58.13 mph (93.56 km/h) |
| 65 mph (104.61 km/h) | 62.98 mph (101.35 km/h) |
| 70 mph (112.65 km/h) | 67.82 mph (109.15 km/h) |
| 75 mph (120.7 km/h) | 72.67 mph (116.94 km/h) |
| 80 mph (128.75 km/h) | 77.51 mph (124.74 km/h) |
| 85 mph (136.79 km/h) | 82.35 mph (132.54 km/h) |
| 90 mph (144.84 km/h) | 87.2 mph (140.33 km/h) |
| 95 mph (152.89 km/h) | 92.04 mph (148.13 km/h) |
| 100 mph (160.93 km/h) | 96.89 mph (155.93 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1394 | 1620 | 1744 | 1821 | 1904 | 1964 | 2029 | 2106 | 2213 | 2320 | 2438 | 2533 | 2705 | 2895 | 3044 | 3139 | 3192 | 3388 | 3661 | 4254 |
Better Fuel Economy Factory Ratios Increased Power
