Tire Size Box

235/60R16 vs 255/60R16

255/60R16 compared with 235/60R16

+3.5% diameter, +0.8" width

255/60R16 is 28.05" tall vs 27.10". More than the 3% rule of thumb, so check carefully before switching.

27.1"16" rim5.6"9.3" wide
235/60R16 (solid) compared with 255/60R16 (dashed outline), drawn to scale

With 255/60R16 tires, when your speedometer says 60 mph you are really going

62.1 mph

255/60R16 is +0.94 inches (+3.5%) in overall diameter. That is more than the 3% most shops and makers recommend.

235/60R16255/60R16Difference%
Overall diameter27.10"28.05"+0.94"+3.5%
Section width9.25"10.04"+0.79"+8.5%
Sidewall height5.55"6.02"+0.47"+8.5%
Circumference85.14"88.11"+2.97"+3.5%
Revolutions per mile744.1719.1−25.1−3.4%

Speedometer difference

If your vehicle came with 235/60R16 and you fit 255/60R16, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.7 mph+0.7 mph
30 mph31.0 mph+1.0 mph
40 mph41.4 mph+1.4 mph
50 mph51.7 mph+1.7 mph
60 mph62.1 mph+2.1 mph
65 mph67.3 mph+2.3 mph
70 mph72.4 mph+2.4 mph
75 mph77.6 mph+2.6 mph
80 mph82.8 mph+2.8 mph

Each size on its own

Questions

Which is bigger, 235/60R16 or 255/60R16?
255/60R16 is taller by 0.94 inches (28.05" vs 27.10"). 255/60R16 is wider by 0.79 inches.
Can I replace 235/60R16 with 255/60R16?
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 255/60R16 change my speedometer?
When your speedometer reads 60 mph with 255/60R16 fitted (calibrated for 235/60R16), your real speed is 62.1 mph. Your odometer will under-count miles by about 3.5%.
Will 255/60R16 lift my vehicle?
Ride height changes by half the diameter difference: +0.47 inches of ground clearance at the axle.

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