Tire Size Box

275/70R16 vs 275/80R16

275/80R16 compared with 275/70R16

+6.9% diameter, 0.0" width

275/80R16 is 33.32" tall vs 31.16". More than the 3% rule of thumb, so check carefully before switching.

31.2"16" rim7.6"10.8" wide
275/70R16 (solid) compared with 275/80R16 (dashed outline), drawn to scale

With 275/80R16 tires, when your speedometer says 60 mph you are really going

64.2 mph

275/80R16 is +2.17 inches (+6.9%) in overall diameter. That is more than the 3% most shops and makers recommend.

275/70R16275/80R16Difference%
Overall diameter31.16"33.32"+2.17"+6.9%
Section width10.83"10.83"0.00"0.0%
Sidewall height7.58"8.66"+1.08"+14.3%
Circumference97.88"104.69"+6.80"+6.9%
Revolutions per mile647.3605.2−42.1−6.5%

Speedometer difference

If your vehicle came with 275/70R16 and you fit 275/80R16, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph21.4 mph+1.4 mph
30 mph32.1 mph+2.1 mph
40 mph42.8 mph+2.8 mph
50 mph53.5 mph+3.5 mph
60 mph64.2 mph+4.2 mph
65 mph69.5 mph+4.5 mph
70 mph74.9 mph+4.9 mph
75 mph80.2 mph+5.2 mph
80 mph85.6 mph+5.6 mph

Each size on its own

Questions

Which is bigger, 275/70R16 or 275/80R16?
275/80R16 is taller by 2.17 inches (33.32" vs 31.16"). 275/70R16 is the same width.
Can I replace 275/70R16 with 275/80R16?
It is not recommended without checking carefully. The diameter difference is +6.9%, 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 275/80R16 change my speedometer?
When your speedometer reads 60 mph with 275/80R16 fitted (calibrated for 275/70R16), your real speed is 64.2 mph. Your odometer will under-count miles by about 6.9%.
Will 275/80R16 lift my vehicle?
Ride height changes by half the diameter difference: +1.08 inches of ground clearance at the axle.

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