Tire Size Box

255/65R19 vs 275/65R19

275/65R19 compared with 255/65R19

+3.2% diameter, +0.8" width

275/65R19 is 33.07" tall vs 32.05". More than the 3% rule of thumb, so check carefully before switching.

32.1"19" rim6.5"10.0" wide
255/65R19 (solid) compared with 275/65R19 (dashed outline), drawn to scale

With 275/65R19 tires, when your speedometer says 60 mph you are really going

61.9 mph

275/65R19 is +1.02 inches (+3.2%) in overall diameter. That is more than the 3% most shops and makers recommend.

255/65R19275/65R19Difference%
Overall diameter32.05"33.07"+1.02"+3.2%
Section width10.04"10.83"+0.79"+7.8%
Sidewall height6.53"7.04"+0.51"+7.8%
Circumference100.69"103.91"+3.22"+3.2%
Revolutions per mile629.2609.8−19.5−3.1%

Speedometer difference

If your vehicle came with 255/65R19 and you fit 275/65R19, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.6 mph+0.6 mph
30 mph31.0 mph+1.0 mph
40 mph41.3 mph+1.3 mph
50 mph51.6 mph+1.6 mph
60 mph61.9 mph+1.9 mph
65 mph67.1 mph+2.1 mph
70 mph72.2 mph+2.2 mph
75 mph77.4 mph+2.4 mph
80 mph82.6 mph+2.6 mph

Each size on its own

Questions

Which is bigger, 255/65R19 or 275/65R19?
275/65R19 is taller by 1.02 inches (33.07" vs 32.05"). 275/65R19 is wider by 0.79 inches.
Can I replace 255/65R19 with 275/65R19?
It is not recommended without checking carefully. The diameter difference is +3.2%, 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 275/65R19 change my speedometer?
When your speedometer reads 60 mph with 275/65R19 fitted (calibrated for 255/65R19), your real speed is 61.9 mph. Your odometer will under-count miles by about 3.2%.
Will 275/65R19 lift my vehicle?
Ride height changes by half the diameter difference: +0.51 inches of ground clearance at the axle.

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