CarSpecsHQ

205/55R17 vs 245/50R17

245/50R17 is a safe swap for 205/55R17 by the usual ±3% rule: the diameter differs by +2.97%.

17" rim
205/55R17 25.88" · 245/50R17 26.65" · drawn to scale

Side by side

205/55R17245/50R17Difference
Overall diameter25.88"26.65"+0.77" (+2.97%)
Section width205 mm245 mm+40 mm
Sidewall4.44"4.82"+0.38"
Rim17"17"same
Circumference81.3"83.7"+2.4"
Revs per mile779757-22
Ride height——+0.38"
Speedometer reads 60 mph60.061.8+1.8 mph

Speedometer and odometer

020406080100120 reads 60 · actual 61.8 mph

With 245/50R17 on a car calibrated for 205/55R17, the speedometer reads 58.3 mph when you're really doing 60, and the odometer under-counts by 3.0%.

Speedo showsActual speed
30 mph30.9 mph
45 mph46.3 mph
60 mph61.8 mph
70 mph72.1 mph
80 mph82.4 mph

Other sizes close to 205/55R17

Questions

Can I replace 205/55R17 with 245/50R17?

245/50R17 is a safe swap for 205/55R17 by the usual ±3% rule: the diameter differs by +2.97%.

What's the difference between 205/55R17 and 245/50R17?

245/50R17 is 0.77" taller and 40 mm wider; the sidewall is +0.38". At an indicated 60 mph you'd actually be doing 61.8 mph.

Will 245/50R17 fit on 205/55R17 wheels?

Both use a 17" rim, so the wheel diameter matches; check the wheel's width range for a 245 mm tire and the fender clearance.