Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 180/55-18 | 180/40-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 25.8 (655.2) | 23.67 (601.2) | -2.13 (-54) -8.2% |
| Width inches (mm) | 7.09 (180) | 7.09 (180) | 0 (0) 0% |
| Circum. inches (mm) | 81.04 (2058.37) | 74.36 (1888.73) | -6.68 (-169.65) -8.2% |
| Sidewall Height inches (mm) | 3.9 (99) | 2.83 (72) | -1.06 (-27) -27.3% |
| Revolutions per mile (km) | 781.85 (485.82) | 852.08 (529.46) | 70.23 (43.64) 9% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 18.35 mph (29.53 km/h) |
| 25 mph (40.23 km/h) | 22.94 mph (36.92 km/h) |
| 30 mph (48.28 km/h) | 27.53 mph (44.3 km/h) |
| 35 mph (56.33 km/h) | 32.12 mph (51.68 km/h) |
| 40 mph (64.37 km/h) | 36.7 mph (59.07 km/h) |
| 45 mph (72.42 km/h) | 41.29 mph (66.45 km/h) |
| 50 mph (80.47 km/h) | 45.88 mph (73.84 km/h) |
| 55 mph (88.51 km/h) | 50.47 mph (81.22 km/h) |
| 60 mph (96.56 km/h) | 55.05 mph (88.6 km/h) |
| 65 mph (104.61 km/h) | 59.64 mph (95.99 km/h) |
| 70 mph (112.65 km/h) | 64.23 mph (103.37 km/h) |
| 75 mph (120.7 km/h) | 68.82 mph (110.75 km/h) |
| 80 mph (128.75 km/h) | 73.41 mph (118.14 km/h) |
| 85 mph (136.79 km/h) | 77.99 mph (125.52 km/h) |
| 90 mph (144.84 km/h) | 82.58 mph (132.9 km/h) |
| 95 mph (152.89 km/h) | 87.17 mph (140.29 km/h) |
| 100 mph (160.93 km/h) | 91.76 mph (147.67 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2168 | 2519 | 2713 | 2833 | 2962 | 3054 | 3156 | 3276 | 3442 | 3608 | 3792 | 3940 | 4208 | 4503 | 4734 | 4881 | 4964 | 5269 | 5693 | 6616 |
Better Fuel Economy Factory Ratios Increased Power
