CarSpecsHQ

255/55R18 vs 265/60R18

265/60R18 is outside the ±3% rule as a replacement for 255/55R18: the diameter differs by +5.08%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

18" rim
255/55R18 29.04" · 265/60R18 30.52" · drawn to scale

Side by side

255/55R18265/60R18Difference
Overall diameter29.04"30.52"+1.48" (+5.08%)
Section width255 mm265 mm+10 mm
Sidewall5.52"6.26"+0.74"
Rim18"18"same
Circumference91.2"95.9"+4.6"
Revs per mile694661-34
Ride height——+0.74"
Speedometer reads 60 mph60.063.1+3.1 mph

Speedometer and odometer

020406080100120 reads 60 · actual 63.1 mph

With 265/60R18 on a car calibrated for 255/55R18, the speedometer reads 57.1 mph when you're really doing 60, and the odometer under-counts by 5.1%.

Speedo showsActual speed
30 mph31.5 mph
45 mph47.3 mph
60 mph63.1 mph
70 mph73.6 mph
80 mph84.1 mph

Other sizes close to 255/55R18

Questions

Can I replace 255/55R18 with 265/60R18?

265/60R18 is outside the ±3% rule as a replacement for 255/55R18: the diameter differs by +5.08%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 255/55R18 and 265/60R18?

265/60R18 is 1.48" taller and 10 mm wider; the sidewall is +0.74". At an indicated 60 mph you'd actually be doing 63.1 mph.

Will 265/60R18 fit on 255/55R18 wheels?

Both use a 18" rim, so the wheel diameter matches; check the wheel's width range for a 265 mm tire and the fender clearance.