TireSizesFinder

245/55R20 vs 265/40R22

265/40R22 is 0.26 in (6.7 mm) shorter than 245/55R20, a −0.86% diameter difference. With the speedometer set for 245/55R20, an indicated 60 mph is 59.5 mph on 265/40R22.

Is this a safe swap?

Diameter difference −0.86%: under 1%

By overall diameter alone, 265/40R22 is a near match for 245/55R20; 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: 245/55R20 (30.61 in) vs 265/40R22 (30.35 in)245/55R2030.61 in × 9.65 in265/40R2230.35 in × 10.43 in
Side profile and tread width, drawn to the same scale.
245/55R20 vs 265/40R22 differences
Measurement245/55R20265/40R22Difference% diff
Overall diameter30.61 in (777.5 mm)30.35 in (770.8 mm)−0.26 in (−6.7 mm)−0.86%
Sidewall height5.31 in (134.8 mm)4.17 in (106.0 mm)−1.13 in (−28.7 mm)−21.34%
Section width9.65 in (245.0 mm)10.43 in (265.0 mm)+0.79 in (+20.0 mm)+8.16%
Circumference96.16 in (2,442.6 mm)95.34 in (2,421.5 mm)−0.83 in (−21.0 mm)−0.86%
Revolutions per mile659665+6+0.87%
True speed with the speedometer calibrated for 245/55R20
IndicatedActual on 245/55R20Actual on 265/40R22Difference
30 mph30.0 mph29.7 mph−0.3 mph
60 mph60.0 mph59.5 mph−0.5 mph
75 mph75.0 mph74.4 mph−0.6 mph

Ride-height change: 265/40R22 lowers the vehicle by 0.13 in (3.4 mm) at the axle (half the −6.7 mm diameter difference).

265/40R22 is 0.26 in shorter than 245/55R20 and 20 mm wider, a 0.86% difference in overall diameter.

With the speedometer calibrated for 245/55R20, an indicated 60 mph is actually 59.5 mph on 265/40R22, and revolutions per mile change from 659 to 665.

265/40R22 mounts on a 22-inch wheel, a plus-2 fitment from the 20-inch wheel of 245/55R20.

Size pages

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