Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 125/80-17 | 235/40-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 24.87 (631.8) | 25.4 (645.2) | 0.53 (13.4) 2.1% |
| Width inches (mm) | 4.92 (125) | 9.25 (235) | 4.33 (110) 88% |
| Circum. inches (mm) | 78.14 (1984.86) | 79.8 (2026.96) | 1.66 (42.1) 2.1% |
| Sidewall Height inches (mm) | 3.94 (100) | 3.7 (94) | -0.24 (-6) -6% |
| Revolutions per mile (km) | 810.81 (503.81) | 793.97 (493.35) | -16.84 (-10.46) -2.1% |
235/40-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.42 mph (32.87 km/h) |
| 25 mph (40.23 km/h) | 25.53 mph (41.09 km/h) |
| 30 mph (48.28 km/h) | 30.64 mph (49.3 km/h) |
| 35 mph (56.33 km/h) | 35.74 mph (57.52 km/h) |
| 40 mph (64.37 km/h) | 40.85 mph (65.74 km/h) |
| 45 mph (72.42 km/h) | 45.95 mph (73.96 km/h) |
| 50 mph (80.47 km/h) | 51.06 mph (82.17 km/h) |
| 55 mph (88.51 km/h) | 56.17 mph (90.39 km/h) |
| 60 mph (96.56 km/h) | 61.27 mph (98.61 km/h) |
| 65 mph (104.61 km/h) | 66.38 mph (106.83 km/h) |
| 70 mph (112.65 km/h) | 71.48 mph (115.04 km/h) |
| 75 mph (120.7 km/h) | 76.59 mph (123.26 km/h) |
| 80 mph (128.75 km/h) | 81.7 mph (131.48 km/h) |
| 85 mph (136.79 km/h) | 86.8 mph (139.7 km/h) |
| 90 mph (144.84 km/h) | 91.91 mph (147.91 km/h) |
| 95 mph (152.89 km/h) | 97.01 mph (156.13 km/h) |
| 100 mph (160.93 km/h) | 102.12 mph (164.35 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2021 | 2347 | 2528 | 2640 | 2760 | 2846 | 2940 | 3052 | 3207 | 3362 | 3534 | 3671 | 3921 | 4196 | 4411 | 4548 | 4626 | 4909 | 5305 | 6165 |
Better Fuel Economy Factory Ratios Increased Power
