245/65R17 vs 245/70R17
245/70R17 is outside the ±3% rule as a replacement for 245/65R17: the diameter differs by +3.27%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.
Speedometer and odometer
With 245/70R17 on a car calibrated for 245/65R17, the speedometer reads 58.1 mph when you're really doing 60, and the odometer under-counts by 3.3%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 31.0 mph |
| 45 mph | 46.5 mph |
| 60 mph | 62.0 mph |
| 70 mph | 72.3 mph |
| 80 mph | 82.6 mph |
Other sizes close to 245/65R17
- 245/65R17 vs 225/65R17-3.47%
- 245/65R17 vs 235/65R17-1.73%
- 245/65R17 vs 245/60R18+0.12%
- 245/65R17 vs 225/75R16-0.85%
- 245/65R17 vs 265/65R17+3.47%
- 245/65R17 vs 235/60R17-4.86%
- 245/65R17 vs 245/70R16-0.12%
- 245/65R17 vs 255/65R17+1.73%
- 245/65R17 vs 235/75R17+4.53%
- 245/65R17 vs 235/70R17+1.40%
- 245/65R17 vs 255/60R17-1.67%
- 245/65R17 vs 225/75R17+2.53%
Questions
Can I replace 245/65R17 with 245/70R17?
245/70R17 is outside the ±3% rule as a replacement for 245/65R17: the diameter differs by +3.27%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.
What's the difference between 245/65R17 and 245/70R17?
245/70R17 is 0.96" taller and 0 mm wider; the sidewall is +0.48". At an indicated 60 mph you'd actually be doing 62.0 mph.
Will 245/70R17 fit on 245/65R17 wheels?
Both use a 17" rim, so the wheel diameter matches; check the wheel's width range for a 245 mm tire and the fender clearance.