Tire Size Box

295/70R18 vs 295/75R18

295/75R18 compared with 295/70R18

+3.4% diameter, 0.0" width

295/75R18 is 35.42" tall vs 34.26". More than the 3% rule of thumb, so check carefully before switching.

34.3"18" rim8.1"11.6" wide
295/70R18 (solid) compared with 295/75R18 (dashed outline), drawn to scale

With 295/75R18 tires, when your speedometer says 60 mph you are really going

62.0 mph

295/75R18 is +1.16 inches (+3.4%) in overall diameter. That is more than the 3% most shops and makers recommend.

295/70R18295/75R18Difference%
Overall diameter34.26"35.42"+1.16"+3.4%
Section width11.61"11.61"0.00"0.0%
Sidewall height8.13"8.71"+0.58"+7.1%
Circumference107.63"111.28"+3.65"+3.4%
Revolutions per mile588.7569.4−19.3−3.3%

Speedometer difference

If your vehicle came with 295/70R18 and you fit 295/75R18, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.7 mph+0.7 mph
30 mph31.0 mph+1.0 mph
40 mph41.4 mph+1.4 mph
50 mph51.7 mph+1.7 mph
60 mph62.0 mph+2.0 mph
65 mph67.2 mph+2.2 mph
70 mph72.4 mph+2.4 mph
75 mph77.5 mph+2.5 mph
80 mph82.7 mph+2.7 mph

Each size on its own

Questions

Which is bigger, 295/70R18 or 295/75R18?
295/75R18 is taller by 1.16 inches (35.42" vs 34.26"). 295/70R18 is the same width.
Can I replace 295/70R18 with 295/75R18?
It is not recommended without checking carefully. The diameter difference is +3.4%, 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 295/75R18 change my speedometer?
When your speedometer reads 60 mph with 295/75R18 fitted (calibrated for 295/70R18), your real speed is 62.0 mph. Your odometer will under-count miles by about 3.4%.
Will 295/75R18 lift my vehicle?
Ride height changes by half the diameter difference: +0.58 inches of ground clearance at the axle.

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