Tire Size Box

215/75R15 vs 215/85R15

215/85R15 compared with 215/75R15

+6.1% diameter, 0.0" width

215/85R15 is 29.39" tall vs 27.70". More than the 3% rule of thumb, so check carefully before switching.

27.7"15" rim6.3"8.5" wide
215/75R15 (solid) compared with 215/85R15 (dashed outline), drawn to scale

With 215/85R15 tires, when your speedometer says 60 mph you are really going

63.7 mph

215/85R15 is +1.69 inches (+6.1%) in overall diameter. That is more than the 3% most shops and makers recommend.

215/75R15215/85R15Difference%
Overall diameter27.70"29.39"+1.69"+6.1%
Section width8.46"8.46"0.00"0.0%
Sidewall height6.35"7.19"+0.85"+13.3%
Circumference87.01"92.33"+5.32"+6.1%
Revolutions per mile728.2686.2−41.9−5.8%

Speedometer difference

If your vehicle came with 215/75R15 and you fit 215/85R15, 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 mph53.1 mph+3.1 mph
60 mph63.7 mph+3.7 mph
65 mph69.0 mph+4.0 mph
70 mph74.3 mph+4.3 mph
75 mph79.6 mph+4.6 mph
80 mph84.9 mph+4.9 mph

Each size on its own

Questions

Which is bigger, 215/75R15 or 215/85R15?
215/85R15 is taller by 1.69 inches (29.39" vs 27.70"). 215/75R15 is the same width.
Can I replace 215/75R15 with 215/85R15?
It is not recommended without checking carefully. The diameter difference is +6.1%, 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 215/85R15 change my speedometer?
When your speedometer reads 60 mph with 215/85R15 fitted (calibrated for 215/75R15), your real speed is 63.7 mph. Your odometer will under-count miles by about 6.1%.
Will 215/85R15 lift my vehicle?
Ride height changes by half the diameter difference: +0.85 inches of ground clearance at the axle.

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