Tire Size Box

245/75R17 vs 265/75R17

265/75R17 compared with 245/75R17

+3.8% diameter, +0.8" width

265/75R17 is 32.65" tall vs 31.47". More than the 3% rule of thumb, so check carefully before switching.

31.5"17" rim7.2"9.6" wide
245/75R17 (solid) compared with 265/75R17 (dashed outline), drawn to scale

With 265/75R17 tires, when your speedometer says 60 mph you are really going

62.3 mph

265/75R17 is +1.18 inches (+3.8%) in overall diameter. That is more than the 3% most shops and makers recommend.

245/75R17265/75R17Difference%
Overall diameter31.47"32.65"+1.18"+3.8%
Section width9.65"10.43"+0.79"+8.2%
Sidewall height7.23"7.82"+0.59"+8.2%
Circumference98.86"102.57"+3.71"+3.8%
Revolutions per mile640.9617.7−23.2−3.6%

Speedometer difference

If your vehicle came with 245/75R17 and you fit 265/75R17, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.8 mph+0.8 mph
30 mph31.1 mph+1.1 mph
40 mph41.5 mph+1.5 mph
50 mph51.9 mph+1.9 mph
60 mph62.3 mph+2.3 mph
65 mph67.4 mph+2.4 mph
70 mph72.6 mph+2.6 mph
75 mph77.8 mph+2.8 mph
80 mph83.0 mph+3.0 mph

Each size on its own

Questions

Which is bigger, 245/75R17 or 265/75R17?
265/75R17 is taller by 1.18 inches (32.65" vs 31.47"). 265/75R17 is wider by 0.79 inches.
Can I replace 245/75R17 with 265/75R17?
It is not recommended without checking carefully. The diameter difference is +3.8%, 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 265/75R17 change my speedometer?
When your speedometer reads 60 mph with 265/75R17 fitted (calibrated for 245/75R17), your real speed is 62.3 mph. Your odometer will under-count miles by about 3.8%.
Will 265/75R17 lift my vehicle?
Ride height changes by half the diameter difference: +0.59 inches of ground clearance at the axle.

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