Tire Size Box

175/65R16 vs 175/75R16

175/75R16 compared with 175/65R16

+5.5% diameter, 0.0" width

175/75R16 is 26.33" tall vs 24.96". More than the 3% rule of thumb, so check carefully before switching.

25.0"16" rim4.5"6.9" wide
175/65R16 (solid) compared with 175/75R16 (dashed outline), drawn to scale

With 175/75R16 tires, when your speedometer says 60 mph you are really going

63.3 mph

175/75R16 is +1.38 inches (+5.5%) in overall diameter. That is more than the 3% most shops and makers recommend.

175/65R16175/75R16Difference%
Overall diameter24.96"26.33"+1.38"+5.5%
Section width6.89"6.89"0.00"0.0%
Sidewall height4.48"5.17"+0.69"+15.4%
Circumference78.40"82.73"+4.33"+5.5%
Revolutions per mile808.1765.8−42.3−5.2%

Speedometer difference

If your vehicle came with 175/65R16 and you fit 175/75R16, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph21.1 mph+1.1 mph
30 mph31.7 mph+1.7 mph
40 mph42.2 mph+2.2 mph
50 mph52.8 mph+2.8 mph
60 mph63.3 mph+3.3 mph
65 mph68.6 mph+3.6 mph
70 mph73.9 mph+3.9 mph
75 mph79.1 mph+4.1 mph
80 mph84.4 mph+4.4 mph

Each size on its own

Questions

Which is bigger, 175/65R16 or 175/75R16?
175/75R16 is taller by 1.38 inches (26.33" vs 24.96"). 175/65R16 is the same width.
Can I replace 175/65R16 with 175/75R16?
It is not recommended without checking carefully. The diameter difference is +5.5%, 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 175/75R16 change my speedometer?
When your speedometer reads 60 mph with 175/75R16 fitted (calibrated for 175/65R16), your real speed is 63.3 mph. Your odometer will under-count miles by about 5.5%.
Will 175/75R16 lift my vehicle?
Ride height changes by half the diameter difference: +0.69 inches of ground clearance at the axle.

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