Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 165/90-18 | 235/45-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 29.69 (754.2) | 26.33 (668.7) | -3.37 (-85.5) -11.3% |
| Width inches (mm) | 6.5 (165) | 9.25 (235) | 2.76 (70) 42.4% |
| Circum. inches (mm) | 93.28 (2369.39) | 82.71 (2100.78) | -10.58 (-268.61) -11.3% |
| Sidewall Height inches (mm) | 5.85 (148.5) | 4.16 (105.75) | -1.68 (-42.75) -28.8% |
| Revolutions per mile (km) | 679.22 (422.05) | 766.07 (476.01) | 86.85 (53.96) 12.8% |
235/45-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 17.73 mph (28.54 km/h) |
| 25 mph (40.23 km/h) | 22.17 mph (35.67 km/h) |
| 30 mph (48.28 km/h) | 26.6 mph (42.81 km/h) |
| 35 mph (56.33 km/h) | 31.03 mph (49.94 km/h) |
| 40 mph (64.37 km/h) | 35.47 mph (57.08 km/h) |
| 45 mph (72.42 km/h) | 39.9 mph (64.21 km/h) |
| 50 mph (80.47 km/h) | 44.33 mph (71.35 km/h) |
| 55 mph (88.51 km/h) | 48.76 mph (78.48 km/h) |
| 60 mph (96.56 km/h) | 53.2 mph (85.61 km/h) |
| 65 mph (104.61 km/h) | 57.63 mph (92.75 km/h) |
| 70 mph (112.65 km/h) | 62.06 mph (99.88 km/h) |
| 75 mph (120.7 km/h) | 66.5 mph (107.02 km/h) |
| 80 mph (128.75 km/h) | 70.93 mph (114.15 km/h) |
| 85 mph (136.79 km/h) | 75.36 mph (121.29 km/h) |
| 90 mph (144.84 km/h) | 79.8 mph (128.42 km/h) |
| 95 mph (152.89 km/h) | 84.23 mph (135.56 km/h) |
| 100 mph (160.93 km/h) | 88.66 mph (142.69 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1949 | 2265 | 2439 | 2547 | 2663 | 2746 | 2837 | 2945 | 3094 | 3244 | 3410 | 3542 | 3783 | 4048 | 4256 | 4388 | 4463 | 4737 | 5118 | 5948 |
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