CarSpecsHQ

285/60R20 vs 275/65R20

275/65R20 is a safe swap for 285/60R20 by the usual ±3% rule: the diameter differs by +1.82%.

20" rim
285/60R20 33.46" · 275/65R20 34.07" · drawn to scale

Side by side

285/60R20275/65R20Difference
Overall diameter33.46"34.07"+0.61" (+1.82%)
Section width285 mm275 mm-10 mm
Sidewall6.73"7.04"+0.31"
Rim20"20"same
Circumference105.1"107.0"+1.9"
Revs per mile603592-11
Ride height——+0.31"
Speedometer reads 60 mph60.061.1+1.1 mph

Speedometer and odometer

020406080100120 reads 60 · actual 61.1 mph

With 275/65R20 on a car calibrated for 285/60R20, the speedometer reads 58.9 mph when you're really doing 60, and the odometer under-counts by 1.8%.

Speedo showsActual speed
30 mph30.5 mph
45 mph45.8 mph
60 mph61.1 mph
70 mph71.3 mph
80 mph81.5 mph

Other sizes close to 285/60R20

Questions

Can I replace 285/60R20 with 275/65R20?

275/65R20 is a safe swap for 285/60R20 by the usual ±3% rule: the diameter differs by +1.82%.

What's the difference between 285/60R20 and 275/65R20?

275/65R20 is 0.61" taller and 10 mm narrower; the sidewall is +0.31". At an indicated 60 mph you'd actually be doing 61.1 mph.

Will 275/65R20 fit on 285/60R20 wheels?

Both use a 20" rim, so the wheel diameter matches; check the wheel's width range for a 275 mm tire and the fender clearance.