CarSpecsHQ

235/45R17 vs 215/55R17

215/55R17 is outside the ±3% rule as a replacement for 235/45R17: the diameter differs by +3.89%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

17" rim
235/45R17 25.33" · 215/55R17 26.31" · drawn to scale

Side by side

235/45R17215/55R17Difference
Overall diameter25.33"26.31"+0.98" (+3.89%)
Section width235 mm215 mm-20 mm
Sidewall4.16"4.66"+0.49"
Rim17"17"same
Circumference79.6"82.7"+3.1"
Revs per mile796767-30
Ride height——+0.49"
Speedometer reads 60 mph60.062.3+2.3 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.3 mph

With 215/55R17 on a car calibrated for 235/45R17, the speedometer reads 57.8 mph when you're really doing 60, and the odometer under-counts by 3.9%.

Speedo showsActual speed
30 mph31.2 mph
45 mph46.7 mph
60 mph62.3 mph
70 mph72.7 mph
80 mph83.1 mph

Other sizes close to 235/45R17

Questions

Can I replace 235/45R17 with 215/55R17?

215/55R17 is outside the ±3% rule as a replacement for 235/45R17: the diameter differs by +3.89%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 235/45R17 and 215/55R17?

215/55R17 is 0.98" taller and 20 mm narrower; the sidewall is +0.49". At an indicated 60 mph you'd actually be doing 62.3 mph.

Will 215/55R17 fit on 235/45R17 wheels?

Both use a 17" rim, so the wheel diameter matches; check the wheel's width range for a 215 mm tire and the fender clearance.