Tire Size Box

275/65R17 vs 275/75R17

275/75R17 compared with 275/65R17

+7.0% diameter, 0.0" width

275/75R17 is 33.24" tall vs 31.07". More than the 3% rule of thumb, so check carefully before switching.

31.1"17" rim7.0"10.8" wide
275/65R17 (solid) compared with 275/75R17 (dashed outline), drawn to scale

With 275/75R17 tires, when your speedometer says 60 mph you are really going

64.2 mph

275/75R17 is +2.17 inches (+7.0%) in overall diameter. That is more than the 3% most shops and makers recommend.

275/65R17275/75R17Difference%
Overall diameter31.07"33.24"+2.17"+7.0%
Section width10.83"10.83"0.00"0.0%
Sidewall height7.04"8.12"+1.08"+15.4%
Circumference97.62"104.43"+6.80"+7.0%
Revolutions per mile649.0606.7−42.3−6.5%

Speedometer difference

If your vehicle came with 275/65R17 and you fit 275/75R17, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph21.4 mph+1.4 mph
30 mph32.1 mph+2.1 mph
40 mph42.8 mph+2.8 mph
50 mph53.5 mph+3.5 mph
60 mph64.2 mph+4.2 mph
65 mph69.5 mph+4.5 mph
70 mph74.9 mph+4.9 mph
75 mph80.2 mph+5.2 mph
80 mph85.6 mph+5.6 mph

Each size on its own

Questions

Which is bigger, 275/65R17 or 275/75R17?
275/75R17 is taller by 2.17 inches (33.24" vs 31.07"). 275/65R17 is the same width.
Can I replace 275/65R17 with 275/75R17?
It is not recommended without checking carefully. The diameter difference is +7.0%, more than the 3% most shops and makers allow. It will throw off the speedometer and may affect ABS, stability control and clearance.
How much will 275/75R17 change my speedometer?
When your speedometer reads 60 mph with 275/75R17 fitted (calibrated for 275/65R17), your real speed is 64.2 mph. Your odometer will under-count miles by about 7.0%.
Will 275/75R17 lift my vehicle?
Ride height changes by half the diameter difference: +1.08 inches of ground clearance at the axle.

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