Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 305/35-17 | 285/40-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 25.41 (645.3) | 26.98 (685.2) | 1.57 (39.9) 6.2% |
| Width inches (mm) | 12.01 (305) | 11.22 (285) | -0.79 (-20) -6.6% |
| Circum. inches (mm) | 79.81 (2027.27) | 84.75 (2152.62) | 4.94 (125.35) 6.2% |
| Sidewall Height inches (mm) | 4.2 (106.75) | 4.49 (114) | 0.29 (7.25) 6.8% |
| Revolutions per mile (km) | 793.85 (493.27) | 747.62 (464.55) | -46.23 (-28.72) -5.8% |
285/40-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.24 mph (34.18 km/h) |
| 25 mph (40.23 km/h) | 26.55 mph (42.72 km/h) |
| 30 mph (48.28 km/h) | 31.85 mph (51.27 km/h) |
| 35 mph (56.33 km/h) | 37.16 mph (59.81 km/h) |
| 40 mph (64.37 km/h) | 42.47 mph (68.35 km/h) |
| 45 mph (72.42 km/h) | 47.78 mph (76.9 km/h) |
| 50 mph (80.47 km/h) | 53.09 mph (85.44 km/h) |
| 55 mph (88.51 km/h) | 58.4 mph (93.99 km/h) |
| 60 mph (96.56 km/h) | 63.71 mph (102.53 km/h) |
| 65 mph (104.61 km/h) | 69.02 mph (111.08 km/h) |
| 70 mph (112.65 km/h) | 74.33 mph (119.62 km/h) |
| 75 mph (120.7 km/h) | 79.64 mph (128.16 km/h) |
| 80 mph (128.75 km/h) | 84.95 mph (136.71 km/h) |
| 85 mph (136.79 km/h) | 90.26 mph (145.25 km/h) |
| 90 mph (144.84 km/h) | 95.56 mph (153.8 km/h) |
| 95 mph (152.89 km/h) | 100.87 mph (162.34 km/h) |
| 100 mph (160.93 km/h) | 106.18 mph (170.89 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1903 | 2210 | 2380 | 2485 | 2599 | 2680 | 2769 | 2874 | 3020 | 3166 | 3327 | 3457 | 3692 | 3951 | 4153 | 4283 | 4356 | 4623 | 4995 | 5805 |
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