Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 155/70-18 | 185/55-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 26.54 (674.2) | 26.01 (660.7) | -0.53 (-13.5) -2% |
| Width inches (mm) | 6.1 (155) | 7.28 (185) | 1.18 (30) 19.4% |
| Circum. inches (mm) | 83.39 (2118.06) | 81.72 (2075.65) | -1.67 (-42.41) -2% |
| Sidewall Height inches (mm) | 4.27 (108.5) | 4.01 (101.75) | -0.27 (-6.75) -6.2% |
| Revolutions per mile (km) | 759.82 (472.13) | 775.34 (481.78) | 15.53 (9.65) 2% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.6 mph (31.54 km/h) |
| 25 mph (40.23 km/h) | 24.5 mph (39.43 km/h) |
| 30 mph (48.28 km/h) | 29.4 mph (47.31 km/h) |
| 35 mph (56.33 km/h) | 34.3 mph (55.2 km/h) |
| 40 mph (64.37 km/h) | 39.2 mph (63.08 km/h) |
| 45 mph (72.42 km/h) | 44.1 mph (70.97 km/h) |
| 50 mph (80.47 km/h) | 49 mph (78.86 km/h) |
| 55 mph (88.51 km/h) | 53.9 mph (86.74 km/h) |
| 60 mph (96.56 km/h) | 58.8 mph (94.63 km/h) |
| 65 mph (104.61 km/h) | 63.7 mph (102.51 km/h) |
| 70 mph (112.65 km/h) | 68.6 mph (110.4 km/h) |
| 75 mph (120.7 km/h) | 73.5 mph (118.28 km/h) |
| 80 mph (128.75 km/h) | 78.4 mph (126.17 km/h) |
| 85 mph (136.79 km/h) | 83.3 mph (134.06 km/h) |
| 90 mph (144.84 km/h) | 88.2 mph (141.94 km/h) |
| 95 mph (152.89 km/h) | 93.1 mph (149.83 km/h) |
| 100 mph (160.93 km/h) | 98 mph (157.71 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1973 | 2292 | 2468 | 2578 | 2695 | 2779 | 2871 | 2981 | 3132 | 3283 | 3451 | 3585 | 3829 | 4097 | 4307 | 4442 | 4517 | 4794 | 5180 | 6020 |
Better Fuel Economy Factory Ratios Increased Power
