Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 325/80-15 | 38.5/12.5-16 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 35.47 (901) | 38.54 (978.8) | 3.06 (77.8) 8.6% |
| Width inches (mm) | 12.8 (325) | 12.52 (318) | -0.28 (-7) -2.2% |
| Circum. inches (mm) | 111.44 (2830.57) | 121.06 (3074.99) | 9.62 (244.42) 8.6% |
| Sidewall Height inches (mm) | 10.24 (260) | 11.27 (286.2) | 1.03 (26.2) 10.1% |
| Revolutions per mile (km) | 568.56 (353.28) | 523.37 (325.2) | -45.19 (-28.08) -7.9% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.73 mph (34.97 km/h) |
| 25 mph (40.23 km/h) | 27.16 mph (43.71 km/h) |
| 30 mph (48.28 km/h) | 32.59 mph (52.45 km/h) |
| 35 mph (56.33 km/h) | 38.02 mph (61.19 km/h) |
| 40 mph (64.37 km/h) | 43.45 mph (69.93 km/h) |
| 45 mph (72.42 km/h) | 48.89 mph (78.67 km/h) |
| 50 mph (80.47 km/h) | 54.32 mph (87.42 km/h) |
| 55 mph (88.51 km/h) | 59.75 mph (96.16 km/h) |
| 60 mph (96.56 km/h) | 65.18 mph (104.9 km/h) |
| 65 mph (104.61 km/h) | 70.61 mph (113.64 km/h) |
| 70 mph (112.65 km/h) | 76.04 mph (122.38 km/h) |
| 75 mph (120.7 km/h) | 81.48 mph (131.12 km/h) |
| 80 mph (128.75 km/h) | 86.91 mph (139.86 km/h) |
| 85 mph (136.79 km/h) | 92.34 mph (148.61 km/h) |
| 90 mph (144.84 km/h) | 97.77 mph (157.35 km/h) |
| 95 mph (152.89 km/h) | 103.2 mph (166.09 km/h) |
| 100 mph (160.93 km/h) | 108.63 mph (174.83 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1332 | 1547 | 1666 | 1740 | 1819 | 1876 | 1938 | 2012 | 2114 | 2216 | 2329 | 2420 | 2584 | 2766 | 2907 | 2998 | 3049 | 3236 | 3497 | 4064 |
Better Fuel Economy Factory Ratios Increased Power
