CarSpecsHQ

33x12.50R18 vs 295/70R18

295/70R18 is outside the ±3% rule as a replacement for 33x12.50R18: the diameter differs by +3.82%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

18" rim
33x12.50R18 33.00" · 295/70R18 34.26" · drawn to scale

Side by side

33x12.50R18295/70R18Difference
Overall diameter33.00"34.26"+1.26" (+3.82%)
Section width318 mm295 mm-23 mm
Sidewall7.50"8.13"+0.63"
Rim18"18"same
Circumference103.7"107.6"+4.0"
Revs per mile611589-22
Ride height——+0.63"
Speedometer reads 60 mph60.062.3+2.3 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.3 mph

With 295/70R18 on a car calibrated for 33x12.50R18, the speedometer reads 57.8 mph when you're really doing 60, and the odometer under-counts by 3.8%.

Speedo showsActual speed
30 mph31.1 mph
45 mph46.7 mph
60 mph62.3 mph
70 mph72.7 mph
80 mph83.1 mph

Other sizes close to 33x12.50R18

Questions

Can I replace 33x12.50R18 with 295/70R18?

295/70R18 is outside the ±3% rule as a replacement for 33x12.50R18: the diameter differs by +3.82%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 33x12.50R18 and 295/70R18?

295/70R18 is 1.26" taller and 23 mm narrower; the sidewall is +0.63". At an indicated 60 mph you'd actually be doing 62.3 mph.

Will 295/70R18 fit on 33x12.50R18 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.