TireSizesFinder

295/70R17 vs 275/70R18

275/70R18 is 0.10 in (2.6 mm) shorter than 295/70R17, a −0.31% diameter difference. With the speedometer set for 295/70R17, an indicated 60 mph is 59.8 mph on 275/70R18.

Is this a safe swap?

Diameter difference −0.31%: under 1%

By overall diameter alone, 275/70R18 is a near match for 295/70R17; 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: 295/70R17 (33.26 in) vs 275/70R18 (33.16 in)295/70R1733.26 in × 11.61 in275/70R1833.16 in × 10.83 in
Side profile and tread width, drawn to the same scale.
295/70R17 vs 275/70R18 differences
Measurement295/70R17275/70R18Difference% diff
Overall diameter33.26 in (844.8 mm)33.16 in (842.2 mm)−0.10 in (−2.6 mm)−0.31%
Sidewall height8.13 in (206.5 mm)7.58 in (192.5 mm)−0.55 in (−14.0 mm)−6.78%
Section width11.61 in (295.0 mm)10.83 in (275.0 mm)−0.79 in (−20.0 mm)−6.78%
Circumference104.49 in (2,654.0 mm)104.17 in (2,645.8 mm)−0.32 in (−8.2 mm)−0.31%
Revolutions per mile606608+2+0.31%
True speed with the speedometer calibrated for 295/70R17
IndicatedActual on 295/70R17Actual on 275/70R18Difference
30 mph30.0 mph29.9 mph−0.1 mph
60 mph60.0 mph59.8 mph−0.2 mph
75 mph75.0 mph74.8 mph−0.2 mph

Ride-height change: 275/70R18 lowers the vehicle by 0.05 in (1.3 mm) at the axle (half the −2.6 mm diameter difference).

275/70R18 is 0.10 in shorter than 295/70R17 and 20 mm narrower, a 0.31% difference in overall diameter.

With the speedometer calibrated for 295/70R17, an indicated 60 mph is actually 59.8 mph on 275/70R18, and revolutions per mile change from 606 to 608.

275/70R18 mounts on a 18-inch wheel, a plus-1 fitment from the 17-inch wheel of 295/70R17.

Size pages

Other comparisons with 295/70R17

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