Tire Size Box

275/55R16 vs 275/65R16

275/65R16 compared with 275/55R16

+7.8% diameter, 0.0" width

275/65R16 is 30.07" tall vs 27.91". More than the 3% rule of thumb, so check carefully before switching.

27.9"16" rim6.0"10.8" wide
275/55R16 (solid) compared with 275/65R16 (dashed outline), drawn to scale

With 275/65R16 tires, when your speedometer says 60 mph you are really going

64.7 mph

275/65R16 is +2.17 inches (+7.8%) in overall diameter. That is more than the 3% most shops and makers recommend.

275/55R16275/65R16Difference%
Overall diameter27.91"30.07"+2.17"+7.8%
Section width10.83"10.83"0.00"0.0%
Sidewall height5.95"7.04"+1.08"+18.2%
Circumference87.68"94.48"+6.80"+7.8%
Revolutions per mile722.6670.6−52.0−7.2%

Speedometer difference

If your vehicle came with 275/55R16 and you fit 275/65R16, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph21.6 mph+1.6 mph
30 mph32.3 mph+2.3 mph
40 mph43.1 mph+3.1 mph
50 mph53.9 mph+3.9 mph
60 mph64.7 mph+4.7 mph
65 mph70.0 mph+5.0 mph
70 mph75.4 mph+5.4 mph
75 mph80.8 mph+5.8 mph
80 mph86.2 mph+6.2 mph

Each size on its own

Questions

Which is bigger, 275/55R16 or 275/65R16?
275/65R16 is taller by 2.17 inches (30.07" vs 27.91"). 275/55R16 is the same width.
Can I replace 275/55R16 with 275/65R16?
It is not recommended without checking carefully. The diameter difference is +7.8%, 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 275/65R16 change my speedometer?
When your speedometer reads 60 mph with 275/65R16 fitted (calibrated for 275/55R16), your real speed is 64.7 mph. Your odometer will under-count miles by about 7.8%.
Will 275/65R16 lift my vehicle?
Ride height changes by half the diameter difference: +1.08 inches of ground clearance at the axle.

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