285/75R16 vs 285/70R17

285/70R17 is 0.12 in (3.1 mm) shorter than 285/75R16, a −0.37% diameter difference. With the speedometer set for 285/75R16, an indicated 60 mph is 59.8 mph on 285/70R17.

Is this a safe swap?

Diameter difference −0.37%: under 1%

By overall diameter alone, 285/70R17 is a near match for 285/75R16; the speedometer changes by less than 1%. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 285/75R16 (32.83 in) vs 285/70R17 (32.71 in)285/75R1632.83 in × 11.22 in285/70R1732.71 in × 11.22 in
Side profile and tread width, drawn to the same scale.
285/75R16 vs 285/70R17 differences
Measurement285/75R16285/70R17Difference% diff
Overall diameter32.83 in (833.9 mm)32.71 in (830.8 mm)−0.12 in (−3.1 mm)−0.37%
Sidewall height8.42 in (213.8 mm)7.85 in (199.5 mm)−0.56 in (−14.2 mm)−6.67%
Section width11.22 in (285.0 mm)11.22 in (285.0 mm)0.00 in (0.0 mm)0.00%
Circumference103.14 in (2,619.8 mm)102.76 in (2,610.0 mm)−0.38 in (−9.7 mm)−0.37%
Revolutions per mile614617+2+0.37%
True speed with the speedometer calibrated for 285/75R16
IndicatedActual on 285/75R16Actual on 285/70R17Difference
30 mph30.0 mph29.9 mph−0.1 mph
60 mph60.0 mph59.8 mph−0.2 mph
75 mph75.0 mph74.7 mph−0.3 mph

Ride-height change: 285/70R17 lowers the vehicle by 0.06 in (1.6 mm) at the axle (half the −3.1 mm diameter difference).

285/70R17 is 0.12 in shorter than 285/75R16 and the same width, a 0.37% difference in overall diameter.

With the speedometer calibrated for 285/75R16, an indicated 60 mph is actually 59.8 mph on 285/70R17, and revolutions per mile change from 614 to 617.

285/70R17 mounts on a 17-inch wheel, a plus-1 fitment from the 16-inch wheel of 285/75R16.

Size pages

Other comparisons with 285/75R16

Other comparisons with 285/70R17

Source: Calculated from standard tire geometry formulas. Verified . How these numbers are calculated.