CarSpecsHQ

265/65R18 vs 265/70R17

265/70R17 is a safe swap for 265/65R18 by the usual ±3% rule: the diameter differs by +0.14%.

18" → 17"
265/65R18 31.56" · 265/70R17 31.61" · drawn to scale

Side by side

265/65R18265/70R17Difference
Overall diameter31.56"31.61"+0.04" (+0.14%)
Section width265 mm265 mm0 mm
Sidewall6.78"7.30"+0.52"
Rim18"17"-1"
Circumference99.2"99.3"+0.1"
Revs per mile639638-1
Ride height——+0.02"
Speedometer reads 60 mph60.060.1+0.1 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.1 mph

With 265/70R17 on a car calibrated for 265/65R18, the speedometer reads 59.9 mph when you're really doing 60, and the odometer under-counts by 0.1%.

Speedo showsActual speed
30 mph30.0 mph
45 mph45.1 mph
60 mph60.1 mph
70 mph70.1 mph
80 mph80.1 mph

Other sizes close to 265/65R18

Questions

Can I replace 265/65R18 with 265/70R17?

265/70R17 is a safe swap for 265/65R18 by the usual ±3% rule: the diameter differs by +0.14%.

What's the difference between 265/65R18 and 265/70R17?

265/70R17 is 0.04" taller and 0 mm wider; the sidewall is +0.52". At an indicated 60 mph you'd actually be doing 60.1 mph.

Will 265/70R17 fit on 265/65R18 wheels?

No — 265/65R18 needs a 18" wheel and 265/70R17 a 17" wheel. This is a plus/minus-size swap that changes wheels too.