Tire Size Box

225/75R16 vs 225/85R16

225/85R16 compared with 225/75R16

+6.0% diameter, 0.0" width

225/85R16 is 31.06" tall vs 29.29". More than the 3% rule of thumb, so check carefully before switching.

29.3"16" rim6.6"8.9" wide
225/75R16 (solid) compared with 225/85R16 (dashed outline), drawn to scale

With 225/85R16 tires, when your speedometer says 60 mph you are really going

63.6 mph

225/85R16 is +1.77 inches (+6.0%) in overall diameter. That is more than the 3% most shops and makers recommend.

225/75R16225/85R16Difference%
Overall diameter29.29"31.06"+1.77"+6.0%
Section width8.86"8.86"0.00"0.0%
Sidewall height6.64"7.53"+0.89"+13.3%
Circumference92.01"97.57"+5.57"+6.0%
Revolutions per mile688.6649.3−39.3−5.7%

Speedometer difference

If your vehicle came with 225/75R16 and you fit 225/85R16, 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 mph63.6 mph+3.6 mph
65 mph68.9 mph+3.9 mph
70 mph74.2 mph+4.2 mph
75 mph79.5 mph+4.5 mph
80 mph84.8 mph+4.8 mph

Each size on its own

Questions

Which is bigger, 225/75R16 or 225/85R16?
225/85R16 is taller by 1.77 inches (31.06" vs 29.29"). 225/75R16 is the same width.
Can I replace 225/75R16 with 225/85R16?
It is not recommended without checking carefully. The diameter difference is +6.0%, 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 225/85R16 change my speedometer?
When your speedometer reads 60 mph with 225/85R16 fitted (calibrated for 225/75R16), your real speed is 63.6 mph. Your odometer will under-count miles by about 6.0%.
Will 225/85R16 lift my vehicle?
Ride height changes by half the diameter difference: +0.89 inches of ground clearance at the axle.

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