TireSizesFinder

185/60R14 vs 185/55R15

185/55R15 is 0.27 in (6.9 mm) taller than 185/60R14, a +1.19% diameter difference. With the speedometer set for 185/60R14, an indicated 60 mph is 60.7 mph on 185/55R15.

Is this a safe swap?

Diameter difference +1.19%: within the ±3% guideline

By overall diameter alone, 185/55R15 falls inside the ±3% range commonly used as a guideline when replacing 185/60R14. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 185/60R14 (22.74 in) vs 185/55R15 (23.01 in)185/60R1422.74 in × 7.28 in185/55R1523.01 in × 7.28 in
Side profile and tread width, drawn to the same scale.
185/60R14 vs 185/55R15 differences
Measurement185/60R14185/55R15Difference% diff
Overall diameter22.74 in (577.6 mm)23.01 in (584.5 mm)+0.27 in (+6.9 mm)+1.19%
Sidewall height4.37 in (111.0 mm)4.01 in (101.8 mm)−0.36 in (−9.2 mm)−8.33%
Section width7.28 in (185.0 mm)7.28 in (185.0 mm)0.00 in (0.0 mm)0.00%
Circumference71.44 in (1,814.6 mm)72.29 in (1,836.3 mm)+0.85 in (+21.7 mm)+1.19%
Revolutions per mile887876−10−1.18%
True speed with the speedometer calibrated for 185/60R14
IndicatedActual on 185/60R14Actual on 185/55R15Difference
30 mph30.0 mph30.4 mph+0.4 mph
60 mph60.0 mph60.7 mph+0.7 mph
75 mph75.0 mph75.9 mph+0.9 mph

Ride-height change: 185/55R15 raises the vehicle by 0.14 in (3.5 mm) at the axle (half the +6.9 mm diameter difference).

185/55R15 is 0.27 in taller than 185/60R14 and the same width, a 1.19% difference in overall diameter.

With the speedometer calibrated for 185/60R14, an indicated 60 mph is actually 60.7 mph on 185/55R15, and revolutions per mile change from 887 to 876.

185/55R15 mounts on a 15-inch wheel, a plus-1 fitment from the 14-inch wheel of 185/60R14.

Size pages

Other comparisons with 185/60R14

Other comparisons with 185/55R15

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