245/70R17 vs 235/75R17

235/75R17 is 0.37 in (9.5 mm) taller than 245/70R17, a +1.23% diameter difference. With the speedometer set for 245/70R17, an indicated 60 mph is 60.7 mph on 235/75R17.

Is this a safe swap?

Diameter difference +1.23%: within the ±3% guideline

By overall diameter alone, 235/75R17 falls inside the ±3% range commonly used as a guideline when replacing 245/70R17. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 245/70R17 (30.50 in) vs 235/75R17 (30.88 in)245/70R1730.50 in × 9.65 in235/75R1730.88 in × 9.25 in
Side profile and tread width, drawn to the same scale.
245/70R17 vs 235/75R17 differences
Measurement245/70R17235/75R17Difference% diff
Overall diameter30.50 in (774.8 mm)30.88 in (784.3 mm)+0.37 in (+9.5 mm)+1.23%
Sidewall height6.75 in (171.5 mm)6.94 in (176.3 mm)+0.19 in (+4.8 mm)+2.77%
Section width9.65 in (245.0 mm)9.25 in (235.0 mm)−0.39 in (−10.0 mm)−4.08%
Circumference95.83 in (2,434.1 mm)97.01 in (2,464.0 mm)+1.18 in (+29.8 mm)+1.23%
Revolutions per mile661653−8−1.21%
True speed with the speedometer calibrated for 245/70R17
IndicatedActual on 245/70R17Actual on 235/75R17Difference
30 mph30.0 mph30.4 mph+0.4 mph
60 mph60.0 mph60.7 mph+0.7 mph
75 mph75.0 mph75.9 mph+0.9 mph

Ride-height change: 235/75R17 raises the vehicle by 0.19 in (4.8 mm) at the axle (half the +9.5 mm diameter difference).

235/75R17 is 0.37 in taller than 245/70R17 and 10 mm narrower, a 1.23% difference in overall diameter.

With the speedometer calibrated for 245/70R17, an indicated 60 mph is actually 60.7 mph on 235/75R17, and revolutions per mile change from 661 to 653.

Both sizes mount on 17-inch wheels.

Size pages

Other comparisons with 245/70R17

Other comparisons with 235/75R17

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