Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 285/30-18 | 315/30-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 24.73 (628.2) | 25.44 (646.2) | 0.71 (18) 2.9% |
| Width inches (mm) | 11.22 (285) | 12.4 (315) | 1.18 (30) 10.5% |
| Circum. inches (mm) | 77.7 (1973.55) | 79.93 (2030.1) | 2.23 (56.55) 2.9% |
| Sidewall Height inches (mm) | 3.37 (85.5) | 3.72 (94.5) | 0.35 (9) 10.5% |
| Revolutions per mile (km) | 815.46 (506.7) | 792.74 (492.59) | -22.71 (-14.11) -2.8% |
315/30-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.57 mph (33.11 km/h) |
| 25 mph (40.23 km/h) | 25.72 mph (41.39 km/h) |
| 30 mph (48.28 km/h) | 30.86 mph (49.66 km/h) |
| 35 mph (56.33 km/h) | 36 mph (57.94 km/h) |
| 40 mph (64.37 km/h) | 41.15 mph (66.22 km/h) |
| 45 mph (72.42 km/h) | 46.29 mph (74.5 km/h) |
| 50 mph (80.47 km/h) | 51.43 mph (82.77 km/h) |
| 55 mph (88.51 km/h) | 56.58 mph (91.05 km/h) |
| 60 mph (96.56 km/h) | 61.72 mph (99.33 km/h) |
| 65 mph (104.61 km/h) | 66.86 mph (107.6 km/h) |
| 70 mph (112.65 km/h) | 72.01 mph (115.88 km/h) |
| 75 mph (120.7 km/h) | 77.15 mph (124.16 km/h) |
| 80 mph (128.75 km/h) | 82.29 mph (132.44 km/h) |
| 85 mph (136.79 km/h) | 87.44 mph (140.71 km/h) |
| 90 mph (144.84 km/h) | 92.58 mph (148.99 km/h) |
| 95 mph (152.89 km/h) | 97.72 mph (157.27 km/h) |
| 100 mph (160.93 km/h) | 102.87 mph (165.55 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2017 | 2344 | 2524 | 2635 | 2756 | 2841 | 2936 | 3048 | 3202 | 3357 | 3528 | 3666 | 3915 | 4189 | 4404 | 4541 | 4619 | 4902 | 5297 | 6155 |
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