Tire Size Box

265/65R15 vs 265/75R15

265/75R15 compared with 265/65R15

+7.3% diameter, 0.0" width

265/75R15 is 30.65" tall vs 28.56". More than the 3% rule of thumb, so check carefully before switching.

28.6"15" rim6.8"10.4" wide
265/65R15 (solid) compared with 265/75R15 (dashed outline), drawn to scale

With 265/75R15 tires, when your speedometer says 60 mph you are really going

64.4 mph

265/75R15 is +2.09 inches (+7.3%) in overall diameter. That is more than the 3% most shops and makers recommend.

265/65R15265/75R15Difference%
Overall diameter28.56"30.65"+2.09"+7.3%
Section width10.43"10.43"0.00"0.0%
Sidewall height6.78"7.82"+1.04"+15.4%
Circumference89.73"96.29"+6.56"+7.3%
Revolutions per mile706.1658.0−48.1−6.8%

Speedometer difference

If your vehicle came with 265/65R15 and you fit 265/75R15, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph21.5 mph+1.5 mph
30 mph32.2 mph+2.2 mph
40 mph42.9 mph+2.9 mph
50 mph53.7 mph+3.7 mph
60 mph64.4 mph+4.4 mph
65 mph69.7 mph+4.7 mph
70 mph75.1 mph+5.1 mph
75 mph80.5 mph+5.5 mph
80 mph85.8 mph+5.8 mph

Each size on its own

Questions

Which is bigger, 265/65R15 or 265/75R15?
265/75R15 is taller by 2.09 inches (30.65" vs 28.56"). 265/65R15 is the same width.
Can I replace 265/65R15 with 265/75R15?
It is not recommended without checking carefully. The diameter difference is +7.3%, 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 265/75R15 change my speedometer?
When your speedometer reads 60 mph with 265/75R15 fitted (calibrated for 265/65R15), your real speed is 64.4 mph. Your odometer will under-count miles by about 7.3%.
Will 265/75R15 lift my vehicle?
Ride height changes by half the diameter difference: +1.04 inches of ground clearance at the axle.

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