CarSpecsHQ

275/55R17 vs 235/70R17

235/70R17 is outside the ±3% rule as a replacement for 275/55R17: the diameter differs by +3.61%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

17" rim
275/55R17 28.91" · 235/70R17 29.95" · drawn to scale

Side by side

275/55R17235/70R17Difference
Overall diameter28.91"29.95"+1.04" (+3.61%)
Section width275 mm235 mm-40 mm
Sidewall5.95"6.48"+0.52"
Rim17"17"same
Circumference90.8"94.1"+3.3"
Revs per mile698673-24
Ride height——+0.52"
Speedometer reads 60 mph60.062.2+2.2 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.2 mph

With 235/70R17 on a car calibrated for 275/55R17, the speedometer reads 57.9 mph when you're really doing 60, and the odometer under-counts by 3.6%.

Speedo showsActual speed
30 mph31.1 mph
45 mph46.6 mph
60 mph62.2 mph
70 mph72.5 mph
80 mph82.9 mph

Other sizes close to 275/55R17

Questions

Can I replace 275/55R17 with 235/70R17?

235/70R17 is outside the ±3% rule as a replacement for 275/55R17: the diameter differs by +3.61%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 275/55R17 and 235/70R17?

235/70R17 is 1.04" taller and 40 mm narrower; the sidewall is +0.52". At an indicated 60 mph you'd actually be doing 62.2 mph.

Will 235/70R17 fit on 275/55R17 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.