CarSpecsHQ

285/65R18 vs 295/70R18

295/70R18 is outside the ±3% rule as a replacement for 285/65R18: the diameter differs by +5.13%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

18" rim
285/65R18 32.59" · 295/70R18 34.26" · drawn to scale

Side by side

285/65R18295/70R18Difference
Overall diameter32.59"34.26"+1.67" (+5.13%)
Section width285 mm295 mm+10 mm
Sidewall7.29"8.13"+0.84"
Rim18"18"same
Circumference102.4"107.6"+5.3"
Revs per mile619589-30
Ride height——+0.84"
Speedometer reads 60 mph60.063.1+3.1 mph

Speedometer and odometer

020406080100120 reads 60 · actual 63.1 mph

With 295/70R18 on a car calibrated for 285/65R18, the speedometer reads 57.1 mph when you're really doing 60, and the odometer under-counts by 5.1%.

Speedo showsActual speed
30 mph31.5 mph
45 mph47.3 mph
60 mph63.1 mph
70 mph73.6 mph
80 mph84.1 mph

Other sizes close to 285/65R18

Questions

Can I replace 285/65R18 with 295/70R18?

295/70R18 is outside the ±3% rule as a replacement for 285/65R18: the diameter differs by +5.13%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 285/65R18 and 295/70R18?

295/70R18 is 1.67" taller and 10 mm wider; the sidewall is +0.84". At an indicated 60 mph you'd actually be doing 63.1 mph.

Will 295/70R18 fit on 285/65R18 wheels?

Both use a 18" rim, so the wheel diameter matches; check the wheel's width range for a 295 mm tire and the fender clearance.