235/75R16 vs 31x10.50R16

31x10.50R16 is 1.12 in (28.5 mm) taller than 235/75R16, a +3.76% diameter difference. With the speedometer set for 235/75R16, an indicated 60 mph is 62.3 mph on 31x10.50R16.

Is this a safe swap?

Diameter difference +3.76%: outside the ±3% guideline

By overall diameter alone, 31x10.50R16 falls outside the ±3% range commonly used as a guideline when replacing 235/75R16; speedometer and ride-height changes are larger. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 235/75R16 (29.88 in) vs 31x10.50R16 (31.00 in)235/75R1629.88 in × 9.25 in31x10.50R1631.00 in × 10.50 in
Side profile and tread width, drawn to the same scale.
235/75R16 vs 31x10.50R16 differences
Measurement235/75R1631x10.50R16Difference% diff
Overall diameter29.88 in (758.9 mm)31.00 in (787.4 mm)+1.12 in (+28.5 mm)+3.76%
Sidewall height6.94 in (176.3 mm)7.50 in (190.5 mm)+0.56 in (+14.3 mm)+8.09%
Section width9.25 in (235.0 mm)10.50 in (266.7 mm)+1.25 in (+31.7 mm)+13.49%
Circumference93.86 in (2,384.2 mm)97.39 in (2,473.7 mm)+3.53 in (+89.5 mm)+3.76%
Revolutions per mile675651−24−3.62%
True speed with the speedometer calibrated for 235/75R16
IndicatedActual on 235/75R16Actual on 31x10.50R16Difference
30 mph30.0 mph31.1 mph+1.1 mph
60 mph60.0 mph62.3 mph+2.3 mph
75 mph75.0 mph77.8 mph+2.8 mph

Ride-height change: 31x10.50R16 raises the vehicle by 0.56 in (14.3 mm) at the axle (half the +28.5 mm diameter difference).

31x10.50R16 is 1.12 in taller than 235/75R16 and 32 mm wider, a 3.76% difference in overall diameter.

With the speedometer calibrated for 235/75R16, an indicated 60 mph is actually 62.3 mph on 31x10.50R16, and revolutions per mile change from 675 to 651.

Both sizes mount on 16-inch wheels.

Size pages

Other comparisons with 235/75R16

Other comparisons with 31x10.50R16

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