Tire Size Box

335/60R18 vs 335/65R18

335/65R18 compared with 335/60R18

+3.9% diameter, 0.0" width

335/65R18 is 35.15" tall vs 33.83". More than the 3% rule of thumb, so check carefully before switching.

33.8"18" rim7.9"13.2" wide
335/60R18 (solid) compared with 335/65R18 (dashed outline), drawn to scale

With 335/65R18 tires, when your speedometer says 60 mph you are really going

62.3 mph

335/65R18 is +1.32 inches (+3.9%) in overall diameter. That is more than the 3% most shops and makers recommend.

335/60R18335/65R18Difference%
Overall diameter33.83"35.15"+1.32"+3.9%
Section width13.19"13.19"0.00"0.0%
Sidewall height7.91"8.57"+0.66"+8.3%
Circumference106.27"110.41"+4.14"+3.9%
Revolutions per mile596.2573.8−22.4−3.8%

Speedometer difference

If your vehicle came with 335/60R18 and you fit 335/65R18, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.8 mph+0.8 mph
30 mph31.2 mph+1.2 mph
40 mph41.6 mph+1.6 mph
50 mph51.9 mph+1.9 mph
60 mph62.3 mph+2.3 mph
65 mph67.5 mph+2.5 mph
70 mph72.7 mph+2.7 mph
75 mph77.9 mph+2.9 mph
80 mph83.1 mph+3.1 mph

Each size on its own

Questions

Which is bigger, 335/60R18 or 335/65R18?
335/65R18 is taller by 1.32 inches (35.15" vs 33.83"). 335/60R18 is the same width.
Can I replace 335/60R18 with 335/65R18?
It is not recommended without checking carefully. The diameter difference is +3.9%, 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 335/65R18 change my speedometer?
When your speedometer reads 60 mph with 335/65R18 fitted (calibrated for 335/60R18), your real speed is 62.3 mph. Your odometer will under-count miles by about 3.9%.
Will 335/65R18 lift my vehicle?
Ride height changes by half the diameter difference: +0.66 inches of ground clearance at the axle.

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