TireSizesFinder

285/40R22 vs 285/30R24

285/30R24 is 0.24 in (6.2 mm) shorter than 285/40R22, a −0.79% diameter difference. With the speedometer set for 285/40R22, an indicated 60 mph is 59.5 mph on 285/30R24.

Is this a safe swap?

Diameter difference −0.79%: under 1%

By overall diameter alone, 285/30R24 is a near match for 285/40R22; 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: 285/40R22 (30.98 in) vs 285/30R24 (30.73 in)285/40R2230.98 in × 11.22 in285/30R2430.73 in × 11.22 in
Side profile and tread width, drawn to the same scale.
285/40R22 vs 285/30R24 differences
Measurement285/40R22285/30R24Difference% diff
Overall diameter30.98 in (786.8 mm)30.73 in (780.6 mm)−0.24 in (−6.2 mm)−0.79%
Sidewall height4.49 in (114.0 mm)3.37 in (85.5 mm)−1.12 in (−28.5 mm)−25.00%
Section width11.22 in (285.0 mm)11.22 in (285.0 mm)0.00 in (0.0 mm)0.00%
Circumference97.32 in (2,471.8 mm)96.55 in (2,452.3 mm)−0.77 in (−19.5 mm)−0.79%
Revolutions per mile651656+5+0.79%
True speed with the speedometer calibrated for 285/40R22
IndicatedActual on 285/40R22Actual on 285/30R24Difference
30 mph30.0 mph29.8 mph−0.2 mph
60 mph60.0 mph59.5 mph−0.5 mph
75 mph75.0 mph74.4 mph−0.6 mph

Ride-height change: 285/30R24 lowers the vehicle by 0.12 in (3.1 mm) at the axle (half the −6.2 mm diameter difference).

285/30R24 is 0.24 in shorter than 285/40R22 and the same width, a 0.79% difference in overall diameter.

With the speedometer calibrated for 285/40R22, an indicated 60 mph is actually 59.5 mph on 285/30R24, and revolutions per mile change from 651 to 656.

285/30R24 mounts on a 24-inch wheel, a plus-2 fitment from the 22-inch wheel of 285/40R22.

Size pages

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Other comparisons with 285/30R24

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