Section Width115 mm (4.5")
Aspect Ratio35%
Rim Diameter18"
Overall Diameter538 mm (21.2")
Sidewall Height40 mm
Circumference1689 mm
115/35R18 — Buy Tires

Everything to know about the 115/35R18 tire size

Size geometry

A 115/35R18 tire has a 115mm section width and a 35% aspect ratio, mounted on a 18-inch rim. Sidewall height works out to 40.3mm (1.58") and overall outside diameter is 537.7mm (21.17"). At highway speed the tire completes about 592 revolutions per kilometre — your speedometer and odometer were calibrated against this number.

Direct substitute sizes

If 115/35R18 is unavailable, the closest same-diameter substitutes on the same rim are 105/38R18 and 125/32R18. Both keep your speedometer reading within 1% — safe for daily use, ABS, and stability control. Always verify load and speed ratings before swapping.

Plus / minus sizing options

For a 115/35R18 you can upsize to 125/22R19 (plus-one) to fit a larger wheel without changing the speedometer reading, or downsize to 105/50R17 (minus-one) for a softer ride or winter setup. Both stay inside the Âą3% diameter tolerance that ABS and TPMS systems expect.

Vehicle compatibility

0 vehicles in our database run the 115/35R18 tire size from the factory. Aftermarket fitment depends on rim width, offset, and clearance — match these specs to your wheel before purchasing tires.

Vehicles Using 115/35R18

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