CarSpecsHQ

295/40R18 vs 265/45R18

265/45R18 is a safe swap for 295/40R18 by the usual ±3% rule: the diameter differs by +0.36%.

18" rim
295/40R18 27.29" · 265/45R18 27.39" · drawn to scale

Side by side

295/40R18265/45R18Difference
Overall diameter27.29"27.39"+0.10" (+0.36%)
Section width295 mm265 mm-30 mm
Sidewall4.65"4.69"+0.05"
Rim18"18"same
Circumference85.7"86.0"+0.3"
Revs per mile739736-3
Ride height——+0.05"
Speedometer reads 60 mph60.060.2+0.2 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.2 mph

With 265/45R18 on a car calibrated for 295/40R18, the speedometer reads 59.8 mph when you're really doing 60, and the odometer under-counts by 0.4%.

Speedo showsActual speed
30 mph30.1 mph
45 mph45.2 mph
60 mph60.2 mph
70 mph70.3 mph
80 mph80.3 mph

Other sizes close to 295/40R18

Questions

Can I replace 295/40R18 with 265/45R18?

265/45R18 is a safe swap for 295/40R18 by the usual ±3% rule: the diameter differs by +0.36%.

What's the difference between 295/40R18 and 265/45R18?

265/45R18 is 0.10" taller and 30 mm narrower; the sidewall is +0.05". At an indicated 60 mph you'd actually be doing 60.2 mph.

Will 265/45R18 fit on 295/40R18 wheels?

Both use a 18" rim, so the wheel diameter matches; check the wheel's width range for a 265 mm tire and the fender clearance.