265/70R17 vs 305/65R17
305/65R17 is outside the ±3% rule as a replacement for 265/70R17: the diameter differs by +3.18%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.
Speedometer and odometer
With 305/65R17 on a car calibrated for 265/70R17, the speedometer reads 58.2 mph when you're really doing 60, and the odometer under-counts by 3.2%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 31.0 mph |
| 45 mph | 46.4 mph |
| 60 mph | 61.9 mph |
| 70 mph | 72.2 mph |
| 80 mph | 82.5 mph |
Other sizes close to 265/70R17
- 265/70R17 vs 265/75R16+0.14%
- 265/70R17 vs 245/70R17-3.49%
- 265/70R17 vs 285/70R17+3.49%
- 265/70R17 vs 265/65R18-0.14%
- 265/70R17 vs 245/75R17-0.44%
- 265/70R17 vs 265/65R17-3.30%
- 265/70R17 vs 235/85R16+0.39%
- 265/70R17 vs 235/80R17+0.62%
- 265/70R17 vs 255/65R17-4.92%
- 265/70R17 vs 255/70R17-1.74%
- 265/70R17 vs 255/75R17+1.43%
- 265/70R17 vs 235/75R17-2.30%
Questions
Can I replace 265/70R17 with 305/65R17?
305/65R17 is outside the ±3% rule as a replacement for 265/70R17: the diameter differs by +3.18%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.
What's the difference between 265/70R17 and 305/65R17?
305/65R17 is 1.00" taller and 40 mm wider; the sidewall is +0.50". At an indicated 60 mph you'd actually be doing 61.9 mph.
Will 305/65R17 fit on 265/70R17 wheels?
Both use a 17" rim, so the wheel diameter matches; check the wheel's width range for a 305 mm tire and the fender clearance.