Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 120/85-18 | 325/85-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 26.03 (661.2) | 39.75 (1009.7) | 13.72 (348.5) 52.7% |
| Width inches (mm) | 4.72 (120) | 12.8 (325) | 8.07 (205) 170.8% |
| Circum. inches (mm) | 81.78 (2077.22) | 124.88 (3172.07) | 43.1 (1094.85) 52.7% |
| Sidewall Height inches (mm) | 4.02 (102) | 10.88 (276.25) | 6.86 (174.25) 170.8% |
| Revolutions per mile (km) | 774.76 (481.41) | 507.35 (315.25) | -267.41 (-166.16) -34.5% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 30.54 mph (49.15 km/h) |
| 25 mph (40.23 km/h) | 38.18 mph (61.44 km/h) |
| 30 mph (48.28 km/h) | 45.81 mph (73.73 km/h) |
| 35 mph (56.33 km/h) | 53.45 mph (86.02 km/h) |
| 40 mph (64.37 km/h) | 61.08 mph (98.3 km/h) |
| 45 mph (72.42 km/h) | 68.72 mph (110.59 km/h) |
| 50 mph (80.47 km/h) | 76.35 mph (122.88 km/h) |
| 55 mph (88.51 km/h) | 83.99 mph (135.17 km/h) |
| 60 mph (96.56 km/h) | 91.62 mph (147.46 km/h) |
| 65 mph (104.61 km/h) | 99.26 mph (159.74 km/h) |
| 70 mph (112.65 km/h) | 106.9 mph (172.03 km/h) |
| 75 mph (120.7 km/h) | 114.53 mph (184.32 km/h) |
| 80 mph (128.75 km/h) | 122.17 mph (196.61 km/h) |
| 85 mph (136.79 km/h) | 129.8 mph (208.9 km/h) |
| 90 mph (144.84 km/h) | 137.44 mph (221.18 km/h) |
| 95 mph (152.89 km/h) | 145.07 mph (233.47 km/h) |
| 100 mph (160.93 km/h) | 152.71 mph (245.76 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1291 | 1500 | 1615 | 1687 | 1764 | 1819 | 1879 | 1950 | 2049 | 2148 | 2258 | 2346 | 2505 | 2681 | 2818 | 2906 | 2956 | 3137 | 3390 | 3939 |
Better Fuel Economy Factory Ratios Increased Power
