Tire Size Box

215/60R18 vs 215/70R18

215/70R18 compared with 215/60R18

+6.0% diameter, 0.0" width

215/70R18 is 29.85" tall vs 28.16". More than the 3% rule of thumb, so check carefully before switching.

28.2"18" rim5.1"8.5" wide
215/60R18 (solid) compared with 215/70R18 (dashed outline), drawn to scale

With 215/70R18 tires, when your speedometer says 60 mph you are really going

63.6 mph

215/70R18 is +1.69 inches (+6.0%) in overall diameter. That is more than the 3% most shops and makers recommend.

215/60R18215/70R18Difference%
Overall diameter28.16"29.85"+1.69"+6.0%
Section width8.46"8.46"0.00"0.0%
Sidewall height5.08"5.93"+0.85"+16.7%
Circumference88.46"93.78"+5.32"+6.0%
Revolutions per mile716.3675.6−40.6−5.7%

Speedometer difference

If your vehicle came with 215/60R18 and you fit 215/70R18, 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, 215/60R18 or 215/70R18?
215/70R18 is taller by 1.69 inches (29.85" vs 28.16"). 215/60R18 is the same width.
Can I replace 215/60R18 with 215/70R18?
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 215/70R18 change my speedometer?
When your speedometer reads 60 mph with 215/70R18 fitted (calibrated for 215/60R18), your real speed is 63.6 mph. Your odometer will under-count miles by about 6.0%.
Will 215/70R18 lift my vehicle?
Ride height changes by half the diameter difference: +0.85 inches of ground clearance at the axle.

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