TireSizesFinder

31x10.50R16 vs 275/60R18

275/60R18 is 0.01 in (0.2 mm) shorter than 31x10.50R16, a −0.03% diameter difference. With the speedometer set for 31x10.50R16, an indicated 60 mph is 60.0 mph on 275/60R18.

Is this a safe swap?

Diameter difference −0.03%: under 1%

By overall diameter alone, 275/60R18 is a near match for 31x10.50R16; 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: 31x10.50R16 (31.00 in) vs 275/60R18 (30.99 in)31x10.50R1631.00 in × 10.50 in275/60R1830.99 in × 10.83 in
Side profile and tread width, drawn to the same scale.
31x10.50R16 vs 275/60R18 differences
Measurement31x10.50R16275/60R18Difference% diff
Overall diameter31.00 in (787.4 mm)30.99 in (787.2 mm)−0.01 in (−0.2 mm)−0.03%
Sidewall height7.50 in (190.5 mm)6.50 in (165.0 mm)−1.00 in (−25.5 mm)−13.39%
Section width10.50 in (266.7 mm)10.83 in (275.0 mm)+0.33 in (+8.3 mm)+3.11%
Circumference97.39 in (2,473.7 mm)97.36 in (2,473.1 mm)−0.02 in (−0.6 mm)−0.03%
Revolutions per mile6516510+0.03%
True speed with the speedometer calibrated for 31x10.50R16
IndicatedActual on 31x10.50R16Actual on 275/60R18Difference
30 mph30.0 mph30.0 mph0.0 mph
60 mph60.0 mph60.0 mph0.0 mph
75 mph75.0 mph75.0 mph0.0 mph

Ride-height change: 275/60R18 lowers the vehicle by 0.00 in (0.1 mm) at the axle (half the −0.2 mm diameter difference).

275/60R18 is 0.01 in shorter than 31x10.50R16 and 8 mm wider, a 0.03% difference in overall diameter.

With the speedometer calibrated for 31x10.50R16, an indicated 60 mph is actually 60.0 mph on 275/60R18, and revolutions per mile change from 651 to 651.

275/60R18 mounts on a 18-inch wheel, a plus-2 fitment from the 16-inch wheel of 31x10.50R16.

Size pages

Other comparisons with 31x10.50R16

Other comparisons with 275/60R18

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