Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 235/40-18 | 245/30-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 25.4 (645.2) | 25.79 (655) | 0.39 (9.8) 1.5% |
| Width inches (mm) | 9.25 (235) | 9.65 (245) | 0.39 (10) 4.3% |
| Circum. inches (mm) | 79.8 (2026.96) | 81.01 (2057.74) | 1.21 (30.79) 1.5% |
| Sidewall Height inches (mm) | 3.7 (94) | 2.89 (73.5) | -0.81 (-20.5) -21.8% |
| Revolutions per mile (km) | 793.97 (493.35) | 782.09 (485.97) | -11.88 (-7.38) -1.5% |
245/30-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.3 mph (32.68 km/h) |
| 25 mph (40.23 km/h) | 25.38 mph (40.84 km/h) |
| 30 mph (48.28 km/h) | 30.46 mph (49.01 km/h) |
| 35 mph (56.33 km/h) | 35.53 mph (57.18 km/h) |
| 40 mph (64.37 km/h) | 40.61 mph (65.35 km/h) |
| 45 mph (72.42 km/h) | 45.68 mph (73.52 km/h) |
| 50 mph (80.47 km/h) | 50.76 mph (81.69 km/h) |
| 55 mph (88.51 km/h) | 55.84 mph (89.86 km/h) |
| 60 mph (96.56 km/h) | 60.91 mph (98.03 km/h) |
| 65 mph (104.61 km/h) | 65.99 mph (106.2 km/h) |
| 70 mph (112.65 km/h) | 71.06 mph (114.37 km/h) |
| 75 mph (120.7 km/h) | 76.14 mph (122.53 km/h) |
| 80 mph (128.75 km/h) | 81.22 mph (130.7 km/h) |
| 85 mph (136.79 km/h) | 86.29 mph (138.87 km/h) |
| 90 mph (144.84 km/h) | 91.37 mph (147.04 km/h) |
| 95 mph (152.89 km/h) | 96.44 mph (155.21 km/h) |
| 100 mph (160.93 km/h) | 101.52 mph (163.38 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1990 | 2312 | 2490 | 2600 | 2719 | 2803 | 2896 | 3007 | 3159 | 3311 | 3481 | 3616 | 3862 | 4133 | 4345 | 4480 | 4556 | 4836 | 5226 | 6072 |
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