CarSpecsHQ

205/50R17 vs 205/55R17

205/55R17 is outside the ±3% rule as a replacement for 205/50R17: the diameter differs by +3.22%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

17" rim
205/50R17 25.07" · 205/55R17 25.88" · drawn to scale

Side by side

205/50R17205/55R17Difference
Overall diameter25.07"25.88"+0.81" (+3.22%)
Section width205 mm205 mm0 mm
Sidewall4.04"4.44"+0.40"
Rim17"17"same
Circumference78.8"81.3"+2.5"
Revs per mile804779-25
Ride height——+0.40"
Speedometer reads 60 mph60.061.9+1.9 mph

Speedometer and odometer

020406080100120 reads 60 · actual 61.9 mph

With 205/55R17 on a car calibrated for 205/50R17, 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 mph72.3 mph
80 mph82.6 mph

Other sizes close to 205/50R17

Questions

Can I replace 205/50R17 with 205/55R17?

205/55R17 is outside the ±3% rule as a replacement for 205/50R17: the diameter differs by +3.22%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 205/50R17 and 205/55R17?

205/55R17 is 0.81" taller and 0 mm wider; the sidewall is +0.40". At an indicated 60 mph you'd actually be doing 61.9 mph.

Will 205/55R17 fit on 205/50R17 wheels?

Both use a 17" rim, so the wheel diameter matches; check the wheel's width range for a 205 mm tire and the fender clearance.