Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 225/45-21 | 235/55-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.97 (735.9) | 28.18 (715.7) | -0.8 (-20.2) -2.7% |
| Width inches (mm) | 8.86 (225) | 9.25 (235) | 0.39 (10) 4.4% |
| Circum. inches (mm) | 91.02 (2311.9) | 88.52 (2248.44) | -2.5 (-63.46) -2.7% |
| Sidewall Height inches (mm) | 3.99 (101.25) | 5.09 (129.25) | 1.1 (28) 27.7% |
| Revolutions per mile (km) | 696.11 (432.54) | 715.76 (444.75) | 19.65 (12.21) 2.8% |
235/55-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.45 mph (31.3 km/h) |
| 25 mph (40.23 km/h) | 24.31 mph (39.13 km/h) |
| 30 mph (48.28 km/h) | 29.18 mph (46.96 km/h) |
| 35 mph (56.33 km/h) | 34.04 mph (54.78 km/h) |
| 40 mph (64.37 km/h) | 38.9 mph (62.61 km/h) |
| 45 mph (72.42 km/h) | 43.76 mph (70.43 km/h) |
| 50 mph (80.47 km/h) | 48.63 mph (78.26 km/h) |
| 55 mph (88.51 km/h) | 53.49 mph (86.08 km/h) |
| 60 mph (96.56 km/h) | 58.35 mph (93.91 km/h) |
| 65 mph (104.61 km/h) | 63.22 mph (101.74 km/h) |
| 70 mph (112.65 km/h) | 68.08 mph (109.56 km/h) |
| 75 mph (120.7 km/h) | 72.94 mph (117.39 km/h) |
| 80 mph (128.75 km/h) | 77.8 mph (125.21 km/h) |
| 85 mph (136.79 km/h) | 82.67 mph (133.04 km/h) |
| 90 mph (144.84 km/h) | 87.53 mph (140.87 km/h) |
| 95 mph (152.89 km/h) | 92.39 mph (148.69 km/h) |
| 100 mph (160.93 km/h) | 97.26 mph (156.52 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1821 | 2116 | 2279 | 2380 | 2488 | 2566 | 2651 | 2752 | 2891 | 3031 | 3186 | 3310 | 3534 | 3782 | 3976 | 4100 | 4170 | 4426 | 4782 | 5557 |
Better Fuel Economy Factory Ratios Increased Power
