TireSizesFinder

30x9.50R15 vs 245/70R16

245/70R16 is 0.50 in (12.6 mm) shorter than 30x9.50R15, a −1.65% diameter difference. With the speedometer set for 30x9.50R15, an indicated 60 mph is 59.0 mph on 245/70R16.

Is this a safe swap?

Diameter difference −1.65%: within the ±3% guideline

By overall diameter alone, 245/70R16 falls inside the ±3% range commonly used as a guideline when replacing 30x9.50R15. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 30x9.50R15 (30.00 in) vs 245/70R16 (29.50 in)30x9.50R1530.00 in × 9.50 in245/70R1629.50 in × 9.65 in
Side profile and tread width, drawn to the same scale.
30x9.50R15 vs 245/70R16 differences
Measurement30x9.50R15245/70R16Difference% diff
Overall diameter30.00 in (762.0 mm)29.50 in (749.4 mm)−0.50 in (−12.6 mm)−1.65%
Sidewall height7.50 in (190.5 mm)6.75 in (171.5 mm)−0.75 in (−19.0 mm)−9.97%
Section width9.50 in (241.3 mm)9.65 in (245.0 mm)+0.15 in (+3.7 mm)+1.53%
Circumference94.25 in (2,393.9 mm)92.69 in (2,354.3 mm)−1.56 in (−39.6 mm)−1.65%
Revolutions per mile672684+11+1.68%
True speed with the speedometer calibrated for 30x9.50R15
IndicatedActual on 30x9.50R15Actual on 245/70R16Difference
30 mph30.0 mph29.5 mph−0.5 mph
60 mph60.0 mph59.0 mph−1.0 mph
75 mph75.0 mph73.8 mph−1.2 mph

Ride-height change: 245/70R16 lowers the vehicle by 0.25 in (6.3 mm) at the axle (half the −12.6 mm diameter difference).

245/70R16 is 0.50 in shorter than 30x9.50R15 and 4 mm wider, a 1.65% difference in overall diameter.

With the speedometer calibrated for 30x9.50R15, an indicated 60 mph is actually 59.0 mph on 245/70R16, and revolutions per mile change from 672 to 684.

245/70R16 mounts on a 16-inch wheel, a plus-1 fitment from the 15-inch wheel of 30x9.50R15.

Size pages

Other comparisons with 30x9.50R15

Other comparisons with 245/70R16

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