CarSpecsHQ

265/30R20 vs 235/35R20

235/35R20 is a safe swap for 265/30R20 by the usual ±3% rule: the diameter differs by +0.82%.

20" rim
265/30R20 26.26" · 235/35R20 26.48" · drawn to scale

Side by side

265/30R20235/35R20Difference
Overall diameter26.26"26.48"+0.22" (+0.82%)
Section width265 mm235 mm-30 mm
Sidewall3.13"3.24"+0.11"
Rim20"20"same
Circumference82.5"83.2"+0.7"
Revs per mile768762-6
Ride height——+0.11"
Speedometer reads 60 mph60.060.5+0.5 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.5 mph

With 235/35R20 on a car calibrated for 265/30R20, the speedometer reads 59.5 mph when you're really doing 60, and the odometer under-counts by 0.8%.

Speedo showsActual speed
30 mph30.2 mph
45 mph45.4 mph
60 mph60.5 mph
70 mph70.6 mph
80 mph80.7 mph

Other sizes close to 265/30R20

Questions

Can I replace 265/30R20 with 235/35R20?

235/35R20 is a safe swap for 265/30R20 by the usual ±3% rule: the diameter differs by +0.82%.

What's the difference between 265/30R20 and 235/35R20?

235/35R20 is 0.22" taller and 30 mm narrower; the sidewall is +0.11". At an indicated 60 mph you'd actually be doing 60.5 mph.

Will 235/35R20 fit on 265/30R20 wheels?

Both use a 20" rim, so the wheel diameter matches; check the wheel's width range for a 235 mm tire and the fender clearance.