235/60R18 vs 265/60R18
265/60R18 is outside the ±3% rule as a replacement for 235/60R18: the diameter differs by +4.87%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.
Speedometer and odometer
With 265/60R18 on a car calibrated for 235/60R18, the speedometer reads 57.2 mph when you're really doing 60, and the odometer under-counts by 4.9%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 31.5 mph |
| 45 mph | 47.2 mph |
| 60 mph | 62.9 mph |
| 70 mph | 73.4 mph |
| 80 mph | 83.9 mph |
Other sizes close to 235/60R18
- 235/60R18 vs 235/55R19+0.26%
- 235/60R18 vs 235/55R18-3.18%
- 235/60R18 vs 235/65R17-0.26%
- 235/60R18 vs 225/60R18-1.62%
- 235/60R18 vs 255/50R19-0.22%
- 235/60R18 vs 245/60R18+1.62%
- 235/60R18 vs 225/55R18-4.67%
- 235/60R18 vs 255/55R18-0.20%
- 235/60R18 vs 235/65R18+3.18%
- 235/60R18 vs 255/60R18+3.25%
- 235/60R18 vs 245/55R18-1.69%
- 235/60R18 vs 255/60R17-0.19%
Questions
Can I replace 235/60R18 with 265/60R18?
265/60R18 is outside the ±3% rule as a replacement for 235/60R18: the diameter differs by +4.87%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.
What's the difference between 235/60R18 and 265/60R18?
265/60R18 is 1.42" taller and 30 mm wider; the sidewall is +0.71". At an indicated 60 mph you'd actually be doing 62.9 mph.
Will 265/60R18 fit on 235/60R18 wheels?
Both use a 18" rim, so the wheel diameter matches; check the wheel's width range for a 265 mm tire and the fender clearance.