CarSpecsHQ

265/30R20 vs 275/30R20

275/30R20 is a safe swap for 265/30R20 by the usual ±3% rule: the diameter differs by +0.90%.

20" rim
265/30R20 26.26" · 275/30R20 26.50" · drawn to scale

Side by side

265/30R20275/30R20Difference
Overall diameter26.26"26.50"+0.24" (+0.90%)
Section width265 mm275 mm+10 mm
Sidewall3.13"3.25"+0.12"
Rim20"20"same
Circumference82.5"83.2"+0.7"
Revs per mile768761-7
Ride height——+0.12"
Speedometer reads 60 mph60.060.5+0.5 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.5 mph

With 275/30R20 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 0.9%.

Speedo showsActual speed
30 mph30.3 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 275/30R20?

275/30R20 is a safe swap for 265/30R20 by the usual ±3% rule: the diameter differs by +0.90%.

What's the difference between 265/30R20 and 275/30R20?

275/30R20 is 0.24" taller and 10 mm wider; the sidewall is +0.12". At an indicated 60 mph you'd actually be doing 60.5 mph.

Will 275/30R20 fit on 265/30R20 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.