225/60R18 vs 235/60R18 Side-by-side tire size comparison with specs and compatibility
This tire swap is within the safe 3% diameter threshold. It should not cause issues with speedometer accuracy, ABS, or traction control systems.
Full Specifications Comparison
| Specification | 225/60R18 | 235/60R18 | Difference |
|---|---|---|---|
| Overall Diameter | 727.2 mm (28.6") | 739.2 mm (29.1") | +12 mm |
| Section Width | 225 mm (8.9") | 235 mm (9.3") | +10 mm |
| Sidewall Height | 135 mm | 141 mm | +6 mm |
| Circumference | 2284.6 mm | 2322.3 mm | +37.7 mm |
| Revolutions/Mile | 704 | 693 | -11 |
| Aspect Ratio | 60% | 60% | 0% |
| Rim Diameter | 18" | 18" | 0" |
Key Impact Summary
Speedometer Correction Table
When switching from 225/60R18 to 235/60R18, your speedometer will under-read. Here is the correction at common speeds:
| Speedometer Shows | Actual Speed (mph) | Difference |
|---|---|---|
| 30 mph | 30.5 mph | +0.5 mph |
| 40 mph | 40.7 mph | +0.7 mph |
| 50 mph | 50.8 mph | +0.8 mph |
| 60 mph | 61 mph | +1 mph |
| 70 mph | 71.2 mph | +1.2 mph |
| 80 mph | 81.3 mph | +1.3 mph |
| 90 mph | 91.5 mph | +1.5 mph |
| 100 mph | 101.7 mph | +1.7 mph |
| 110 mph | 111.8 mph | +1.8 mph |
| 120 mph | 122 mph | +2 mph |
What This Swap Means
Wider tires (235/60R18): The 10mm wider contact patch provides better grip in dry conditions and improved cornering stability. However, wider tires increase rolling resistance slightly, which may affect fuel economy by 1-2%. They are also more susceptible to hydroplaning in wet conditions.
Taller sidewall: The 6.0mm increase in sidewall height provides a more comfortable ride by absorbing more road imperfections. Taller sidewalls also offer better protection against pothole damage to wheels. The trade-off is slightly less responsive steering feel.
Ground clearance: Increases by 6mm, providing slightly better approach angles for off-road driving and speed bump clearance.