CarSpecsHQ

235/65R17 vs 235/70R17

235/70R17 is outside the ±3% rule as a replacement for 235/65R17: the diameter differs by +3.19%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

17" rim
235/65R17 29.03" · 235/70R17 29.95" · drawn to scale

Side by side

235/65R17235/70R17Difference
Overall diameter29.03"29.95"+0.93" (+3.19%)
Section width235 mm235 mm0 mm
Sidewall6.01"6.48"+0.46"
Rim17"17"same
Circumference91.2"94.1"+2.9"
Revs per mile695673-21
Ride height——+0.46"
Speedometer reads 60 mph60.061.9+1.9 mph

Speedometer and odometer

020406080100120 reads 60 · actual 61.9 mph

With 235/70R17 on a car calibrated for 235/65R17, the speedometer reads 58.1 mph when you're really doing 60, and the odometer under-counts by 3.2%.

Speedo showsActual speed
30 mph31.0 mph
45 mph46.4 mph
60 mph61.9 mph
70 mph72.2 mph
80 mph82.5 mph

Other sizes close to 235/65R17

Questions

Can I replace 235/65R17 with 235/70R17?

235/70R17 is outside the ±3% rule as a replacement for 235/65R17: the diameter differs by +3.19%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 235/65R17 and 235/70R17?

235/70R17 is 0.93" taller and 0 mm wider; the sidewall is +0.46". At an indicated 60 mph you'd actually be doing 61.9 mph.

Will 235/70R17 fit on 235/65R17 wheels?

Both use a 17" rim, so the wheel diameter matches; check the wheel's width range for a 235 mm tire and the fender clearance.