TireSizesFinder

295/40R20 vs 295/30R22

295/30R22 is 0.32 in (8.2 mm) shorter than 295/40R20, a −1.10% diameter difference. With the speedometer set for 295/40R20, an indicated 60 mph is 59.3 mph on 295/30R22.

Is this a safe swap?

Diameter difference −1.10%: within the ±3% guideline

By overall diameter alone, 295/30R22 falls inside the ±3% range commonly used as a guideline when replacing 295/40R20. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 295/40R20 (29.29 in) vs 295/30R22 (28.97 in)295/40R2029.29 in × 11.61 in295/30R2228.97 in × 11.61 in
Side profile and tread width, drawn to the same scale.
295/40R20 vs 295/30R22 differences
Measurement295/40R20295/30R22Difference% diff
Overall diameter29.29 in (744.0 mm)28.97 in (735.8 mm)−0.32 in (−8.2 mm)−1.10%
Sidewall height4.65 in (118.0 mm)3.48 in (88.5 mm)−1.16 in (−29.5 mm)−25.00%
Section width11.61 in (295.0 mm)11.61 in (295.0 mm)0.00 in (0.0 mm)0.00%
Circumference92.02 in (2,337.3 mm)91.01 in (2,311.6 mm)−1.01 in (−25.8 mm)−1.10%
Revolutions per mile689696+8+1.11%
True speed with the speedometer calibrated for 295/40R20
IndicatedActual on 295/40R20Actual on 295/30R22Difference
30 mph30.0 mph29.7 mph−0.3 mph
60 mph60.0 mph59.3 mph−0.7 mph
75 mph75.0 mph74.2 mph−0.8 mph

Ride-height change: 295/30R22 lowers the vehicle by 0.16 in (4.1 mm) at the axle (half the −8.2 mm diameter difference).

295/30R22 is 0.32 in shorter than 295/40R20 and the same width, a 1.10% difference in overall diameter.

With the speedometer calibrated for 295/40R20, an indicated 60 mph is actually 59.3 mph on 295/30R22, and revolutions per mile change from 689 to 696.

295/30R22 mounts on a 22-inch wheel, a plus-2 fitment from the 20-inch wheel of 295/40R20.

Size pages

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