CarSpecsHQ

225/45R17 vs 255/45R17

255/45R17 is outside the ±3% rule as a replacement for 225/45R17: the diameter differs by +4.26%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

17" rim
225/45R17 24.97" · 255/45R17 26.04" · drawn to scale

Side by side

225/45R17255/45R17Difference
Overall diameter24.97"26.04"+1.06" (+4.26%)
Section width225 mm255 mm+30 mm
Sidewall3.99"4.52"+0.53"
Rim17"17"same
Circumference78.5"81.8"+3.3"
Revs per mile808775-33
Ride height——+0.53"
Speedometer reads 60 mph60.062.6+2.6 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.6 mph

With 255/45R17 on a car calibrated for 225/45R17, the speedometer reads 57.6 mph when you're really doing 60, and the odometer under-counts by 4.3%.

Speedo showsActual speed
30 mph31.3 mph
45 mph46.9 mph
60 mph62.6 mph
70 mph73.0 mph
80 mph83.4 mph

Other sizes close to 225/45R17

Questions

Can I replace 225/45R17 with 255/45R17?

255/45R17 is outside the ±3% rule as a replacement for 225/45R17: the diameter differs by +4.26%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 225/45R17 and 255/45R17?

255/45R17 is 1.06" taller and 30 mm wider; the sidewall is +0.53". At an indicated 60 mph you'd actually be doing 62.6 mph.

Will 255/45R17 fit on 225/45R17 wheels?

Both use a 17" rim, so the wheel diameter matches; check the wheel's width range for a 255 mm tire and the fender clearance.