Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 155/85-18 | 185/85-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.37 (720.7) | 30.38 (771.7) | 2.01 (51) 7.1% |
| Width inches (mm) | 6.1 (155) | 7.28 (185) | 1.18 (30) 19.4% |
| Circum. inches (mm) | 89.14 (2264.15) | 95.45 (2424.37) | 6.31 (160.22) 7.1% |
| Sidewall Height inches (mm) | 5.19 (131.75) | 6.19 (157.25) | 1 (25.5) 19.4% |
| Revolutions per mile (km) | 710.8 (441.67) | 663.82 (412.48) | -46.97 (-29.19) -6.6% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.42 mph (34.46 km/h) |
| 25 mph (40.23 km/h) | 26.77 mph (43.08 km/h) |
| 30 mph (48.28 km/h) | 32.12 mph (51.7 km/h) |
| 35 mph (56.33 km/h) | 37.48 mph (60.31 km/h) |
| 40 mph (64.37 km/h) | 42.83 mph (68.93 km/h) |
| 45 mph (72.42 km/h) | 48.18 mph (77.55 km/h) |
| 50 mph (80.47 km/h) | 53.54 mph (86.16 km/h) |
| 55 mph (88.51 km/h) | 58.89 mph (94.78 km/h) |
| 60 mph (96.56 km/h) | 64.25 mph (103.39 km/h) |
| 65 mph (104.61 km/h) | 69.6 mph (112.01 km/h) |
| 70 mph (112.65 km/h) | 74.95 mph (120.63 km/h) |
| 75 mph (120.7 km/h) | 80.31 mph (129.24 km/h) |
| 80 mph (128.75 km/h) | 85.66 mph (137.86 km/h) |
| 85 mph (136.79 km/h) | 91.01 mph (146.47 km/h) |
| 90 mph (144.84 km/h) | 96.37 mph (155.09 km/h) |
| 95 mph (152.89 km/h) | 101.72 mph (163.71 km/h) |
| 100 mph (160.93 km/h) | 107.08 mph (172.32 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1689 | 1962 | 2113 | 2207 | 2308 | 2379 | 2458 | 2552 | 2681 | 2811 | 2954 | 3069 | 3278 | 3508 | 3688 | 3803 | 3867 | 4105 | 4435 | 5154 |
Better Fuel Economy Factory Ratios Increased Power
