Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 120/85-18 | 28/8.5-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 26.03 (661.2) | 27.99 (711.04) | 1.96 (49.84) 7.5% |
| Width inches (mm) | 4.72 (120) | 8.5 (216) | 3.78 (96) 80% |
| Circum. inches (mm) | 81.78 (2077.22) | 87.94 (2233.8) | 6.16 (156.58) 7.5% |
| Sidewall Height inches (mm) | 4.02 (102) | 4 (101.52) | -0.02 (-0.48) -0.5% |
| Revolutions per mile (km) | 774.76 (481.41) | 720.45 (447.67) | -54.31 (-33.74) -7% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.51 mph (34.61 km/h) |
| 25 mph (40.23 km/h) | 26.88 mph (43.27 km/h) |
| 30 mph (48.28 km/h) | 32.26 mph (51.92 km/h) |
| 35 mph (56.33 km/h) | 37.64 mph (60.57 km/h) |
| 40 mph (64.37 km/h) | 43.02 mph (69.23 km/h) |
| 45 mph (72.42 km/h) | 48.39 mph (77.88 km/h) |
| 50 mph (80.47 km/h) | 53.77 mph (86.53 km/h) |
| 55 mph (88.51 km/h) | 59.15 mph (95.19 km/h) |
| 60 mph (96.56 km/h) | 64.52 mph (103.84 km/h) |
| 65 mph (104.61 km/h) | 69.9 mph (112.49 km/h) |
| 70 mph (112.65 km/h) | 75.28 mph (121.15 km/h) |
| 75 mph (120.7 km/h) | 80.65 mph (129.8 km/h) |
| 80 mph (128.75 km/h) | 86.03 mph (138.45 km/h) |
| 85 mph (136.79 km/h) | 91.41 mph (147.11 km/h) |
| 90 mph (144.84 km/h) | 96.78 mph (155.76 km/h) |
| 95 mph (152.89 km/h) | 102.16 mph (164.41 km/h) |
| 100 mph (160.93 km/h) | 107.54 mph (173.07 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1833 | 2130 | 2294 | 2395 | 2504 | 2582 | 2668 | 2770 | 2910 | 3050 | 3207 | 3331 | 3558 | 3807 | 4002 | 4127 | 4197 | 4455 | 4814 | 5594 |
Better Fuel Economy Factory Ratios Increased Power
