Tire Size Box

295/65R18 vs 295/70R18

295/70R18 compared with 295/65R18

+3.5% diameter, 0.0" width

295/70R18 is 34.26" tall vs 33.10". More than the 3% rule of thumb, so check carefully before switching.

33.1"18" rim7.5"11.6" wide
295/65R18 (solid) compared with 295/70R18 (dashed outline), drawn to scale

With 295/70R18 tires, when your speedometer says 60 mph you are really going

62.1 mph

295/70R18 is +1.16 inches (+3.5%) in overall diameter. That is more than the 3% most shops and makers recommend.

295/65R18295/70R18Difference%
Overall diameter33.10"34.26"+1.16"+3.5%
Section width11.61"11.61"0.00"0.0%
Sidewall height7.55"8.13"+0.58"+7.7%
Circumference103.98"107.63"+3.65"+3.5%
Revolutions per mile609.3588.7−20.7−3.4%

Speedometer difference

If your vehicle came with 295/65R18 and you fit 295/70R18, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.7 mph+0.7 mph
30 mph31.1 mph+1.1 mph
40 mph41.4 mph+1.4 mph
50 mph51.8 mph+1.8 mph
60 mph62.1 mph+2.1 mph
65 mph67.3 mph+2.3 mph
70 mph72.5 mph+2.5 mph
75 mph77.6 mph+2.6 mph
80 mph82.8 mph+2.8 mph

Each size on its own

Questions

Which is bigger, 295/65R18 or 295/70R18?
295/70R18 is taller by 1.16 inches (34.26" vs 33.10"). 295/65R18 is the same width.
Can I replace 295/65R18 with 295/70R18?
It is not recommended without checking carefully. The diameter difference is +3.5%, 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 295/70R18 change my speedometer?
When your speedometer reads 60 mph with 295/70R18 fitted (calibrated for 295/65R18), your real speed is 62.1 mph. Your odometer will under-count miles by about 3.5%.
Will 295/70R18 lift my vehicle?
Ride height changes by half the diameter difference: +0.58 inches of ground clearance at the axle.

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