235/75R17 vs 255/60R19

255/60R19 is 0.17 in (4.3 mm) taller than 235/75R17, a +0.55% diameter difference. With the speedometer set for 235/75R17, an indicated 60 mph is 60.3 mph on 255/60R19.

Is this a safe swap?

Diameter difference +0.55%: under 1%

By overall diameter alone, 255/60R19 is a near match for 235/75R17; the speedometer changes by less than 1%. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

Side profile and tread width, drawn to the same scale.

235/75R17 vs 255/60R19 differences
Measurement	235/75R17	255/60R19	Difference	% diff
Overall diameter	30.88 in (784.3 mm)	31.05 in (788.6 mm)	+0.17 in (+4.3 mm)	+0.55%
Sidewall height	6.94 in (176.3 mm)	6.02 in (153.0 mm)	−0.92 in (−23.2 mm)	−13.19%
Section width	9.25 in (235.0 mm)	10.04 in (255.0 mm)	+0.79 in (+20.0 mm)	+8.51%
Circumference	97.01 in (2,464.0 mm)	97.54 in (2,477.5 mm)	+0.53 in (+13.5 mm)	+0.55%
Revolutions per mile	653	650	−4	−0.55%

True speed with the speedometer calibrated for 235/75R17
Indicated	Actual on 235/75R17	Actual on 255/60R19	Difference
30 mph	30.0 mph	30.2 mph	+0.2 mph
60 mph	60.0 mph	60.3 mph	+0.3 mph
75 mph	75.0 mph	75.4 mph	+0.4 mph

Ride-height change: 255/60R19 raises the vehicle by 0.08 in (2.1 mm) at the axle (half the +4.3 mm diameter difference).

255/60R19 is 0.17 in taller than 235/75R17 and 20 mm wider, a 0.55% difference in overall diameter.

With the speedometer calibrated for 235/75R17, an indicated 60 mph is actually 60.3 mph on 255/60R19, and revolutions per mile change from 653 to 650.

255/60R19 mounts on a 19-inch wheel, a plus-2 fitment from the 17-inch wheel of 235/75R17.

Size pages

Other comparisons with 235/75R17

Other comparisons with 255/60R19

Source: Calculated from standard tire geometry formulas. Verified 2026-09-27. How these numbers are calculated.