CarSpecsHQ

335/25R20 vs 285/30R20

285/30R20 is a safe swap for 335/25R20 by the usual ±3% rule: the diameter differs by +0.52%.

20" rim
335/25R20 26.59" · 285/30R20 26.73" · drawn to scale

Side by side

335/25R20285/30R20Difference
Overall diameter26.59"26.73"+0.14" (+0.52%)
Section width335 mm285 mm-50 mm
Sidewall3.30"3.37"+0.07"
Rim20"20"same
Circumference83.5"84.0"+0.4"
Revs per mile758754-4
Ride height——+0.07"
Speedometer reads 60 mph60.060.3+0.3 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.3 mph

With 285/30R20 on a car calibrated for 335/25R20, the speedometer reads 59.7 mph when you're really doing 60, and the odometer under-counts by 0.5%.

Speedo showsActual speed
30 mph30.2 mph
45 mph45.2 mph
60 mph60.3 mph
70 mph70.4 mph
80 mph80.4 mph

Other sizes close to 335/25R20

Questions

Can I replace 335/25R20 with 285/30R20?

285/30R20 is a safe swap for 335/25R20 by the usual ±3% rule: the diameter differs by +0.52%.

What's the difference between 335/25R20 and 285/30R20?

285/30R20 is 0.14" taller and 50 mm narrower; the sidewall is +0.07". At an indicated 60 mph you'd actually be doing 60.3 mph.

Will 285/30R20 fit on 335/25R20 wheels?

Both use a 20" rim, so the wheel diameter matches; check the wheel's width range for a 285 mm tire and the fender clearance.