Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 120/85-18 | 185/50-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 26.03 (661.2) | 25.28 (642.2) | -0.75 (-19) -2.9% |
| Width inches (mm) | 4.72 (120) | 7.28 (185) | 2.56 (65) 54.2% |
| Circum. inches (mm) | 81.78 (2077.22) | 79.43 (2017.53) | -2.35 (-59.69) -2.9% |
| Sidewall Height inches (mm) | 4.02 (102) | 3.64 (92.5) | -0.37 (-9.5) -9.3% |
| Revolutions per mile (km) | 774.76 (481.41) | 797.68 (495.65) | 22.92 (14.24) 3% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.43 mph (31.26 km/h) |
| 25 mph (40.23 km/h) | 24.28 mph (39.08 km/h) |
| 30 mph (48.28 km/h) | 29.14 mph (46.89 km/h) |
| 35 mph (56.33 km/h) | 33.99 mph (54.71 km/h) |
| 40 mph (64.37 km/h) | 38.85 mph (62.52 km/h) |
| 45 mph (72.42 km/h) | 43.71 mph (70.34 km/h) |
| 50 mph (80.47 km/h) | 48.56 mph (78.16 km/h) |
| 55 mph (88.51 km/h) | 53.42 mph (85.97 km/h) |
| 60 mph (96.56 km/h) | 58.28 mph (93.79 km/h) |
| 65 mph (104.61 km/h) | 63.13 mph (101.6 km/h) |
| 70 mph (112.65 km/h) | 67.99 mph (109.42 km/h) |
| 75 mph (120.7 km/h) | 72.84 mph (117.23 km/h) |
| 80 mph (128.75 km/h) | 77.7 mph (125.05 km/h) |
| 85 mph (136.79 km/h) | 82.56 mph (132.86 km/h) |
| 90 mph (144.84 km/h) | 87.41 mph (140.68 km/h) |
| 95 mph (152.89 km/h) | 92.27 mph (148.49 km/h) |
| 100 mph (160.93 km/h) | 97.13 mph (156.31 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2030 | 2358 | 2540 | 2652 | 2773 | 2859 | 2954 | 3067 | 3222 | 3377 | 3550 | 3688 | 3939 | 4215 | 4431 | 4570 | 4647 | 4932 | 5330 | 6193 |
Better Fuel Economy Factory Ratios Increased Power
