215/45R16 vs 215/40R17

215/40R17 is 0.15 in (3.9 mm) taller than 215/45R16, a +0.65% diameter difference. With the speedometer set for 215/45R16, an indicated 60 mph is 60.4 mph on 215/40R17.

Is this a safe swap?

Diameter difference +0.65%: under 1%

By overall diameter alone, 215/40R17 is a near match for 215/45R16; 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: 215/45R16 (23.62 in) vs 215/40R17 (23.77 in)215/45R1623.62 in × 8.46 in215/40R1723.77 in × 8.46 in
Side profile and tread width, drawn to the same scale.
215/45R16 vs 215/40R17 differences
Measurement215/45R16215/40R17Difference% diff
Overall diameter23.62 in (599.9 mm)23.77 in (603.8 mm)+0.15 in (+3.9 mm)+0.65%
Sidewall height3.81 in (96.8 mm)3.39 in (86.0 mm)−0.42 in (−10.7 mm)−11.11%
Section width8.46 in (215.0 mm)8.46 in (215.0 mm)0.00 in (0.0 mm)0.00%
Circumference74.20 in (1,884.6 mm)74.68 in (1,896.9 mm)+0.48 in (+12.3 mm)+0.65%
Revolutions per mile854848−6−0.65%
True speed with the speedometer calibrated for 215/45R16
IndicatedActual on 215/45R16Actual on 215/40R17Difference
30 mph30.0 mph30.2 mph+0.2 mph
60 mph60.0 mph60.4 mph+0.4 mph
75 mph75.0 mph75.5 mph+0.5 mph

Ride-height change: 215/40R17 raises the vehicle by 0.08 in (1.9 mm) at the axle (half the +3.9 mm diameter difference).

215/40R17 is 0.15 in taller than 215/45R16 and the same width, a 0.65% difference in overall diameter.

With the speedometer calibrated for 215/45R16, an indicated 60 mph is actually 60.4 mph on 215/40R17, and revolutions per mile change from 854 to 848.

215/40R17 mounts on a 17-inch wheel, a plus-1 fitment from the 16-inch wheel of 215/45R16.

Size pages

Other comparisons with 215/45R16

Other comparisons with 215/40R17

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