CarSpecsHQ

265/60R18 vs 285/60R18

285/60R18 is outside the ±3% rule as a replacement for 265/60R18: the diameter differs by +3.10%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

18" rim
265/60R18 30.52" · 285/60R18 31.46" · drawn to scale

Side by side

265/60R18285/60R18Difference
Overall diameter30.52"31.46"+0.94" (+3.10%)
Section width265 mm285 mm+20 mm
Sidewall6.26"6.73"+0.47"
Rim18"18"same
Circumference95.9"98.8"+3.0"
Revs per mile661641-20
Ride height——+0.47"
Speedometer reads 60 mph60.061.9+1.9 mph

Speedometer and odometer

020406080100120 reads 60 · actual 61.9 mph

With 285/60R18 on a car calibrated for 265/60R18, the speedometer reads 58.2 mph when you're really doing 60, and the odometer under-counts by 3.1%.

Speedo showsActual speed
30 mph30.9 mph
45 mph46.4 mph
60 mph61.9 mph
70 mph72.2 mph
80 mph82.5 mph

Other sizes close to 265/60R18

Questions

Can I replace 265/60R18 with 285/60R18?

285/60R18 is outside the ±3% rule as a replacement for 265/60R18: the diameter differs by +3.10%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 265/60R18 and 285/60R18?

285/60R18 is 0.94" taller and 20 mm wider; the sidewall is +0.47". At an indicated 60 mph you'd actually be doing 61.9 mph.

Will 285/60R18 fit on 265/60R18 wheels?

Both use a 18" rim, so the wheel diameter matches; check the wheel's width range for a 285 mm tire and the fender clearance.