CarSpecsHQ

285/70R17 vs 285/75R17

285/75R17 is outside the ±3% rule as a replacement for 285/70R17: the diameter differs by +3.43%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

17" rim
285/70R17 32.71" · 285/75R17 33.83" · drawn to scale

Side by side

285/70R17285/75R17Difference
Overall diameter32.71"33.83"+1.12" (+3.43%)
Section width285 mm285 mm0 mm
Sidewall7.85"8.42"+0.56"
Rim17"17"same
Circumference102.8"106.3"+3.5"
Revs per mile617596-20
Ride height——+0.56"
Speedometer reads 60 mph60.062.1+2.1 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.1 mph

With 285/75R17 on a car calibrated for 285/70R17, the speedometer reads 58.0 mph when you're really doing 60, and the odometer under-counts by 3.4%.

Speedo showsActual speed
30 mph31.0 mph
45 mph46.5 mph
60 mph62.1 mph
70 mph72.4 mph
80 mph82.7 mph

Other sizes close to 285/70R17

Questions

Can I replace 285/70R17 with 285/75R17?

285/75R17 is outside the ±3% rule as a replacement for 285/70R17: the diameter differs by +3.43%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 285/70R17 and 285/75R17?

285/75R17 is 1.12" taller and 0 mm wider; the sidewall is +0.56". At an indicated 60 mph you'd actually be doing 62.1 mph.

Will 285/75R17 fit on 285/70R17 wheels?

Both use a 17" rim, so the wheel diameter matches; check the wheel's width range for a 285 mm tire and the fender clearance.