235/75R17 vs 255/75R17
255/75R17 is outside the ±3% rule as a replacement for 235/75R17: the diameter differs by +3.83%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.
Speedometer and odometer
With 255/75R17 on a car calibrated for 235/75R17, the speedometer reads 57.8 mph when you're really doing 60, and the odometer under-counts by 3.8%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 31.1 mph |
| 45 mph | 46.7 mph |
| 60 mph | 62.3 mph |
| 70 mph | 72.7 mph |
| 80 mph | 83.1 mph |
Other sizes close to 235/75R17
- 235/75R17 vs 265/70R17+2.36%
- 235/75R17 vs 245/70R17-1.21%
- 235/75R17 vs 245/65R17-4.34%
- 235/75R17 vs 245/75R17+1.91%
- 235/75R17 vs 265/65R17-1.02%
- 235/75R17 vs 265/70R16-0.88%
- 235/75R17 vs 235/80R17+3.00%
- 235/75R17 vs 255/65R18+0.56%
- 235/75R17 vs 255/65R17-2.68%
- 235/75R17 vs 255/70R17+0.57%
- 235/75R17 vs 275/70R17+4.14%
- 235/75R17 vs 235/70R17-3.00%
Questions
Can I replace 235/75R17 with 255/75R17?
255/75R17 is outside the ±3% rule as a replacement for 235/75R17: the diameter differs by +3.83%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.
What's the difference between 235/75R17 and 255/75R17?
255/75R17 is 1.18" taller and 20 mm wider; the sidewall is +0.59". At an indicated 60 mph you'd actually be doing 62.3 mph.
Will 255/75R17 fit on 235/75R17 wheels?
Both use a 17" rim, so the wheel diameter matches; check the wheel's width range for a 255 mm tire and the fender clearance.