CarSpecsHQ

265/45R20 vs 275/45R20

275/45R20 is a safe swap for 265/45R20 by the usual ±3% rule: the diameter differs by +1.21%.

20" rim
265/45R20 29.39" · 275/45R20 29.74" · drawn to scale

Side by side

265/45R20275/45R20Difference
Overall diameter29.39"29.74"+0.35" (+1.21%)
Section width265 mm275 mm+10 mm
Sidewall4.69"4.87"+0.18"
Rim20"20"same
Circumference92.3"93.4"+1.1"
Revs per mile686678-8
Ride height——+0.18"
Speedometer reads 60 mph60.060.7+0.7 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.7 mph

With 275/45R20 on a car calibrated for 265/45R20, the speedometer reads 59.3 mph when you're really doing 60, and the odometer under-counts by 1.2%.

Speedo showsActual speed
30 mph30.4 mph
45 mph45.5 mph
60 mph60.7 mph
70 mph70.8 mph
80 mph81.0 mph

Other sizes close to 265/45R20

Questions

Can I replace 265/45R20 with 275/45R20?

275/45R20 is a safe swap for 265/45R20 by the usual ±3% rule: the diameter differs by +1.21%.

What's the difference between 265/45R20 and 275/45R20?

275/45R20 is 0.35" taller and 10 mm wider; the sidewall is +0.18". At an indicated 60 mph you'd actually be doing 60.7 mph.

Will 275/45R20 fit on 265/45R20 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.