TireSizesFinder

175/80R13 vs 185/60R15

185/60R15 is 0.28 in (7.2 mm) shorter than 175/80R13, a −1.18% diameter difference. With the speedometer set for 175/80R13, an indicated 60 mph is 59.3 mph on 185/60R15.

Is this a safe swap?

Diameter difference −1.18%: within the ±3% guideline

By overall diameter alone, 185/60R15 falls inside the ±3% range commonly used as a guideline when replacing 175/80R13. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 175/80R13 (24.02 in) vs 185/60R15 (23.74 in)175/80R1324.02 in × 6.89 in185/60R1523.74 in × 7.28 in
Side profile and tread width, drawn to the same scale.
175/80R13 vs 185/60R15 differences
Measurement175/80R13185/60R15Difference% diff
Overall diameter24.02 in (610.2 mm)23.74 in (603.0 mm)−0.28 in (−7.2 mm)−1.18%
Sidewall height5.51 in (140.0 mm)4.37 in (111.0 mm)−1.14 in (−29.0 mm)−20.71%
Section width6.89 in (175.0 mm)7.28 in (185.0 mm)+0.39 in (+10.0 mm)+5.71%
Circumference75.47 in (1,917.0 mm)74.58 in (1,894.4 mm)−0.89 in (−22.6 mm)−1.18%
Revolutions per mile840850+10+1.19%
True speed with the speedometer calibrated for 175/80R13
IndicatedActual on 175/80R13Actual on 185/60R15Difference
30 mph30.0 mph29.6 mph−0.4 mph
60 mph60.0 mph59.3 mph−0.7 mph
75 mph75.0 mph74.1 mph−0.9 mph

Ride-height change: 185/60R15 lowers the vehicle by 0.14 in (3.6 mm) at the axle (half the −7.2 mm diameter difference).

185/60R15 is 0.28 in shorter than 175/80R13 and 10 mm wider, a 1.18% difference in overall diameter.

With the speedometer calibrated for 175/80R13, an indicated 60 mph is actually 59.3 mph on 185/60R15, and revolutions per mile change from 840 to 850.

185/60R15 mounts on a 15-inch wheel, a plus-2 fitment from the 13-inch wheel of 175/80R13.

Size pages

Other comparisons with 175/80R13

Other comparisons with 185/60R15

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