TireSizesFinder

27x8.50R14 vs 225/65R15

225/65R15 is 0.48 in (12.3 mm) shorter than 27x8.50R14, a −1.79% diameter difference. With the speedometer set for 27x8.50R14, an indicated 60 mph is 58.9 mph on 225/65R15.

Is this a safe swap?

Diameter difference −1.79%: within the ±3% guideline

By overall diameter alone, 225/65R15 falls inside the ±3% range commonly used as a guideline when replacing 27x8.50R14. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 27x8.50R14 (27.00 in) vs 225/65R15 (26.52 in)27x8.50R1427.00 in × 8.50 in225/65R1526.52 in × 8.86 in
Side profile and tread width, drawn to the same scale.
27x8.50R14 vs 225/65R15 differences
Measurement27x8.50R14225/65R15Difference% diff
Overall diameter27.00 in (685.8 mm)26.52 in (673.5 mm)−0.48 in (−12.3 mm)−1.79%
Sidewall height6.50 in (165.1 mm)5.76 in (146.3 mm)−0.74 in (−18.8 mm)−11.42%
Section width8.50 in (215.9 mm)8.86 in (225.0 mm)+0.36 in (+9.1 mm)+4.21%
Circumference84.82 in (2,154.5 mm)83.30 in (2,115.9 mm)−1.52 in (−38.6 mm)−1.79%
Revolutions per mile747761+14+1.83%
True speed with the speedometer calibrated for 27x8.50R14
IndicatedActual on 27x8.50R14Actual on 225/65R15Difference
30 mph30.0 mph29.5 mph−0.5 mph
60 mph60.0 mph58.9 mph−1.1 mph
75 mph75.0 mph73.7 mph−1.3 mph

Ride-height change: 225/65R15 lowers the vehicle by 0.24 in (6.1 mm) at the axle (half the −12.3 mm diameter difference).

225/65R15 is 0.48 in shorter than 27x8.50R14 and 9 mm wider, a 1.79% difference in overall diameter.

With the speedometer calibrated for 27x8.50R14, an indicated 60 mph is actually 58.9 mph on 225/65R15, and revolutions per mile change from 747 to 761.

225/65R15 mounts on a 15-inch wheel, a plus-1 fitment from the 14-inch wheel of 27x8.50R14.

Size pages

Other comparisons with 27x8.50R14

Other comparisons with 225/65R15

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