Tire Size Box

215/75R15 vs 235/75R15

235/75R15 compared with 215/75R15

+4.3% diameter, +0.8" width

235/75R15 is 28.88" 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 235/75R15 (dashed outline), drawn to scale

With 235/75R15 tires, when your speedometer says 60 mph you are really going

62.6 mph

235/75R15 is +1.18 inches (+4.3%) in overall diameter. That is more than the 3% most shops and makers recommend.

215/75R15235/75R15Difference%
Overall diameter27.70"28.88"+1.18"+4.3%
Section width8.46"9.25"+0.79"+9.3%
Sidewall height6.35"6.94"+0.59"+9.3%
Circumference87.01"90.72"+3.71"+4.3%
Revolutions per mile728.2698.4−29.8−4.1%

Speedometer difference

If your vehicle came with 215/75R15 and you fit 235/75R15, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.9 mph+0.9 mph
30 mph31.3 mph+1.3 mph
40 mph41.7 mph+1.7 mph
50 mph52.1 mph+2.1 mph
60 mph62.6 mph+2.6 mph
65 mph67.8 mph+2.8 mph
70 mph73.0 mph+3.0 mph
75 mph78.2 mph+3.2 mph
80 mph83.4 mph+3.4 mph

Each size on its own

Questions

Which is bigger, 215/75R15 or 235/75R15?
235/75R15 is taller by 1.18 inches (28.88" vs 27.70"). 235/75R15 is wider by 0.79 inches.
Can I replace 215/75R15 with 235/75R15?
It is not recommended without checking carefully. The diameter difference is +4.3%, 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 235/75R15 change my speedometer?
When your speedometer reads 60 mph with 235/75R15 fitted (calibrated for 215/75R15), your real speed is 62.6 mph. Your odometer will under-count miles by about 4.3%.
Will 235/75R15 lift my vehicle?
Ride height changes by half the diameter difference: +0.59 inches of ground clearance at the axle.

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