Tire Size Box

245/75R16 vs 245/85R16

245/85R16 compared with 245/75R16

+6.3% diameter, 0.0" width

245/85R16 is 32.40" 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 245/85R16 (dashed outline), drawn to scale

With 245/85R16 tires, when your speedometer says 60 mph you are really going

63.8 mph

245/85R16 is +1.93 inches (+6.3%) in overall diameter. That is more than the 3% most shops and makers recommend.

245/75R16245/85R16Difference%
Overall diameter30.47"32.40"+1.93"+6.3%
Section width9.65"9.65"0.00"0.0%
Sidewall height7.23"8.20"+0.96"+13.3%
Circumference95.72"101.78"+6.06"+6.3%
Revolutions per mile661.9622.5−39.4−6.0%

Speedometer difference

If your vehicle came with 245/75R16 and you fit 245/85R16, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph21.3 mph+1.3 mph
30 mph31.9 mph+1.9 mph
40 mph42.5 mph+2.5 mph
50 mph53.2 mph+3.2 mph
60 mph63.8 mph+3.8 mph
65 mph69.1 mph+4.1 mph
70 mph74.4 mph+4.4 mph
75 mph79.7 mph+4.7 mph
80 mph85.1 mph+5.1 mph

Each size on its own

Questions

Which is bigger, 245/75R16 or 245/85R16?
245/85R16 is taller by 1.93 inches (32.40" vs 30.47"). 245/75R16 is the same width.
Can I replace 245/75R16 with 245/85R16?
It is not recommended without checking carefully. The diameter difference is +6.3%, 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 245/85R16 change my speedometer?
When your speedometer reads 60 mph with 245/85R16 fitted (calibrated for 245/75R16), your real speed is 63.8 mph. Your odometer will under-count miles by about 6.3%.
Will 245/85R16 lift my vehicle?
Ride height changes by half the diameter difference: +0.96 inches of ground clearance at the axle.

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