Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 120/85-18 | 245/80-17.5 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 26.03 (661.2) | 32.93 (836.5) | 6.9 (175.3) 26.5% |
| Width inches (mm) | 4.72 (120) | 9.65 (245) | 4.92 (125) 104.2% |
| Circum. inches (mm) | 81.78 (2077.22) | 103.46 (2627.94) | 21.68 (550.72) 26.5% |
| Sidewall Height inches (mm) | 4.02 (102) | 7.72 (196) | 3.7 (94) 92.2% |
| Revolutions per mile (km) | 774.76 (481.41) | 612.4 (380.53) | -162.36 (-100.89) -21% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 25.3 mph (40.72 km/h) |
| 25 mph (40.23 km/h) | 31.63 mph (50.9 km/h) |
| 30 mph (48.28 km/h) | 37.95 mph (61.08 km/h) |
| 35 mph (56.33 km/h) | 44.28 mph (71.26 km/h) |
| 40 mph (64.37 km/h) | 50.6 mph (81.44 km/h) |
| 45 mph (72.42 km/h) | 56.93 mph (91.62 km/h) |
| 50 mph (80.47 km/h) | 63.26 mph (101.8 km/h) |
| 55 mph (88.51 km/h) | 69.58 mph (111.98 km/h) |
| 60 mph (96.56 km/h) | 75.91 mph (122.16 km/h) |
| 65 mph (104.61 km/h) | 82.23 mph (132.34 km/h) |
| 70 mph (112.65 km/h) | 88.56 mph (142.52 km/h) |
| 75 mph (120.7 km/h) | 94.88 mph (152.7 km/h) |
| 80 mph (128.75 km/h) | 101.21 mph (162.88 km/h) |
| 85 mph (136.79 km/h) | 107.54 mph (173.06 km/h) |
| 90 mph (144.84 km/h) | 113.86 mph (183.24 km/h) |
| 95 mph (152.89 km/h) | 120.19 mph (193.42 km/h) |
| 100 mph (160.93 km/h) | 126.51 mph (203.6 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1558 | 1810 | 1950 | 2036 | 2129 | 2195 | 2268 | 2354 | 2474 | 2593 | 2726 | 2832 | 3024 | 3236 | 3402 | 3508 | 3568 | 3787 | 4092 | 4755 |
Better Fuel Economy Factory Ratios Increased Power
