Tire Size Box

265/55R18 vs 265/60R18

265/60R18 compared with 265/55R18

+3.5% diameter, 0.0" width

265/60R18 is 30.52" tall vs 29.48". More than the 3% rule of thumb, so check carefully before switching.

29.5"18" rim5.7"10.4" wide
265/55R18 (solid) compared with 265/60R18 (dashed outline), drawn to scale

With 265/60R18 tires, when your speedometer says 60 mph you are really going

62.1 mph

265/60R18 is +1.04 inches (+3.5%) in overall diameter. That is more than the 3% most shops and makers recommend.

265/55R18265/60R18Difference%
Overall diameter29.48"30.52"+1.04"+3.5%
Section width10.43"10.43"0.00"0.0%
Sidewall height5.74"6.26"+0.52"+9.1%
Circumference92.60"95.88"+3.28"+3.5%
Revolutions per mile684.2660.8−23.4−3.4%

Speedometer difference

If your vehicle came with 265/55R18 and you fit 265/60R18, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.7 mph+0.7 mph
30 mph31.1 mph+1.1 mph
40 mph41.4 mph+1.4 mph
50 mph51.8 mph+1.8 mph
60 mph62.1 mph+2.1 mph
65 mph67.3 mph+2.3 mph
70 mph72.5 mph+2.5 mph
75 mph77.7 mph+2.7 mph
80 mph82.8 mph+2.8 mph

Each size on its own

Questions

Which is bigger, 265/55R18 or 265/60R18?
265/60R18 is taller by 1.04 inches (30.52" vs 29.48"). 265/55R18 is the same width.
Can I replace 265/55R18 with 265/60R18?
It is not recommended without checking carefully. The diameter difference is +3.5%, 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 265/60R18 change my speedometer?
When your speedometer reads 60 mph with 265/60R18 fitted (calibrated for 265/55R18), your real speed is 62.1 mph. Your odometer will under-count miles by about 3.5%.
Will 265/60R18 lift my vehicle?
Ride height changes by half the diameter difference: +0.52 inches of ground clearance at the axle.

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