Tire Size Box

165/75R13 vs 185/75R13

185/75R13 compared with 165/75R13

+5.2% diameter, +0.8" width

185/75R13 is 23.93" tall vs 22.74". More than the 3% rule of thumb, so check carefully before switching.

22.7"13" rim4.9"6.5" wide
165/75R13 (solid) compared with 185/75R13 (dashed outline), drawn to scale

With 185/75R13 tires, when your speedometer says 60 mph you are really going

63.1 mph

185/75R13 is +1.18 inches (+5.2%) in overall diameter. That is more than the 3% most shops and makers recommend.

165/75R13185/75R13Difference%
Overall diameter22.74"23.93"+1.18"+5.2%
Section width6.50"7.28"+0.79"+12.1%
Sidewall height4.87"5.46"+0.59"+12.1%
Circumference71.45"75.16"+3.71"+5.2%
Revolutions per mile886.7843.0−43.8−4.9%

Speedometer difference

If your vehicle came with 165/75R13 and you fit 185/75R13, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph21.0 mph+1.0 mph
30 mph31.6 mph+1.6 mph
40 mph42.1 mph+2.1 mph
50 mph52.6 mph+2.6 mph
60 mph63.1 mph+3.1 mph
65 mph68.4 mph+3.4 mph
70 mph73.6 mph+3.6 mph
75 mph78.9 mph+3.9 mph
80 mph84.2 mph+4.2 mph

Each size on its own

Questions

Which is bigger, 165/75R13 or 185/75R13?
185/75R13 is taller by 1.18 inches (23.93" vs 22.74"). 185/75R13 is wider by 0.79 inches.
Can I replace 165/75R13 with 185/75R13?
It is not recommended without checking carefully. The diameter difference is +5.2%, 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 185/75R13 change my speedometer?
When your speedometer reads 60 mph with 185/75R13 fitted (calibrated for 165/75R13), your real speed is 63.1 mph. Your odometer will under-count miles by about 5.2%.
Will 185/75R13 lift my vehicle?
Ride height changes by half the diameter difference: +0.59 inches of ground clearance at the axle.

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