Tire Size Box

175/70R13 vs 175/80R13

175/80R13 compared with 175/70R13

+6.1% diameter, 0.0" width

175/80R13 is 24.02" tall vs 22.65". More than the 3% rule of thumb, so check carefully before switching.

22.6"13" rim4.8"6.9" wide
175/70R13 (solid) compared with 175/80R13 (dashed outline), drawn to scale

With 175/80R13 tires, when your speedometer says 60 mph you are really going

63.7 mph

175/80R13 is +1.38 inches (+6.1%) in overall diameter. That is more than the 3% most shops and makers recommend.

175/70R13175/80R13Difference%
Overall diameter22.65"24.02"+1.38"+6.1%
Section width6.89"6.89"0.00"0.0%
Sidewall height4.82"5.51"+0.69"+14.3%
Circumference71.14"75.47"+4.33"+6.1%
Revolutions per mile890.6839.5−51.1−5.7%

Speedometer difference

If your vehicle came with 175/70R13 and you fit 175/80R13, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph21.2 mph+1.2 mph
30 mph31.8 mph+1.8 mph
40 mph42.4 mph+2.4 mph
50 mph53.0 mph+3.0 mph
60 mph63.7 mph+3.7 mph
65 mph69.0 mph+4.0 mph
70 mph74.3 mph+4.3 mph
75 mph79.6 mph+4.6 mph
80 mph84.9 mph+4.9 mph

Each size on its own

Questions

Which is bigger, 175/70R13 or 175/80R13?
175/80R13 is taller by 1.38 inches (24.02" vs 22.65"). 175/70R13 is the same width.
Can I replace 175/70R13 with 175/80R13?
It is not recommended without checking carefully. The diameter difference is +6.1%, 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 175/80R13 change my speedometer?
When your speedometer reads 60 mph with 175/80R13 fitted (calibrated for 175/70R13), your real speed is 63.7 mph. Your odometer will under-count miles by about 6.1%.
Will 175/80R13 lift my vehicle?
Ride height changes by half the diameter difference: +0.69 inches of ground clearance at the axle.

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