TireSizesFinder

33x12.50R15 vs 275/70R17

275/70R17 is 0.84 in (21.4 mm) shorter than 33x12.50R15, a −2.55% diameter difference. With the speedometer set for 33x12.50R15, an indicated 60 mph is 58.5 mph on 275/70R17.

Is this a safe swap?

Diameter difference −2.55%: within the ±3% guideline

By overall diameter alone, 275/70R17 falls inside the ±3% range commonly used as a guideline when replacing 33x12.50R15. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 33x12.50R15 (33.00 in) vs 275/70R17 (32.16 in)33x12.50R1533.00 in × 12.50 in275/70R1732.16 in × 10.83 in
Side profile and tread width, drawn to the same scale.
33x12.50R15 vs 275/70R17 differences
Measurement33x12.50R15275/70R17Difference% diff
Overall diameter33.00 in (838.2 mm)32.16 in (816.8 mm)−0.84 in (−21.4 mm)−2.55%
Sidewall height9.00 in (228.6 mm)7.58 in (192.5 mm)−1.42 in (−36.1 mm)−15.79%
Section width12.50 in (317.5 mm)10.83 in (275.0 mm)−1.67 in (−42.5 mm)−13.39%
Circumference103.67 in (2,633.3 mm)101.03 in (2,566.1 mm)−2.65 in (−67.2 mm)−2.55%
Revolutions per mile611627+16+2.62%
True speed with the speedometer calibrated for 33x12.50R15
IndicatedActual on 33x12.50R15Actual on 275/70R17Difference
30 mph30.0 mph29.2 mph−0.8 mph
60 mph60.0 mph58.5 mph−1.5 mph
75 mph75.0 mph73.1 mph−1.9 mph

Ride-height change: 275/70R17 lowers the vehicle by 0.42 in (10.7 mm) at the axle (half the −21.4 mm diameter difference).

275/70R17 is 0.84 in shorter than 33x12.50R15 and 43 mm narrower, a 2.55% difference in overall diameter.

With the speedometer calibrated for 33x12.50R15, an indicated 60 mph is actually 58.5 mph on 275/70R17, and revolutions per mile change from 611 to 627.

275/70R17 mounts on a 17-inch wheel, a plus-2 fitment from the 15-inch wheel of 33x12.50R15.

Size pages

Other comparisons with 33x12.50R15

Other comparisons with 275/70R17

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