Tire Size Box

245/75R16 vs 245/80R16

245/80R16 compared with 245/75R16

+3.2% diameter, 0.0" width

245/80R16 is 31.43" tall vs 30.47". More than the 3% rule of thumb, so check carefully before switching.

30.5"16" rim7.2"9.6" wide
245/75R16 (solid) compared with 245/80R16 (dashed outline), drawn to scale

With 245/80R16 tires, when your speedometer says 60 mph you are really going

61.9 mph

245/80R16 is +0.96 inches (+3.2%) in overall diameter. That is more than the 3% most shops and makers recommend.

245/75R16245/80R16Difference%
Overall diameter30.47"31.43"+0.96"+3.2%
Section width9.65"9.65"0.00"0.0%
Sidewall height7.23"7.72"+0.48"+6.7%
Circumference95.72"98.75"+3.03"+3.2%
Revolutions per mile661.9641.6−20.3−3.1%

Speedometer difference

If your vehicle came with 245/75R16 and you fit 245/80R16, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.6 mph+0.6 mph
30 mph30.9 mph+0.9 mph
40 mph41.3 mph+1.3 mph
50 mph51.6 mph+1.6 mph
60 mph61.9 mph+1.9 mph
65 mph67.1 mph+2.1 mph
70 mph72.2 mph+2.2 mph
75 mph77.4 mph+2.4 mph
80 mph82.5 mph+2.5 mph

Each size on its own

Questions

Which is bigger, 245/75R16 or 245/80R16?
245/80R16 is taller by 0.96 inches (31.43" vs 30.47"). 245/75R16 is the same width.
Can I replace 245/75R16 with 245/80R16?
It is not recommended without checking carefully. The diameter difference is +3.2%, 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 245/80R16 change my speedometer?
When your speedometer reads 60 mph with 245/80R16 fitted (calibrated for 245/75R16), your real speed is 61.9 mph. Your odometer will under-count miles by about 3.2%.
Will 245/80R16 lift my vehicle?
Ride height changes by half the diameter difference: +0.48 inches of ground clearance at the axle.

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