Section Width355 mm (14.0")
Aspect Ratio42%
Rim Diameter18"
Overall Diameter755 mm (29.7")
Sidewall Height149 mm
Circumference2373 mm
355/42R18 — Buy Tires

Everything to know about the 355/42R18 tire size

Size geometry

A 355/42R18 tire has a 355mm section width and a 42% aspect ratio, mounted on a 18-inch rim. Sidewall height works out to 149.1mm (5.87") and overall outside diameter is 755.4mm (29.74"). At highway speed the tire completes about 421 revolutions per kilometre — your speedometer and odometer were calibrated against this number.

Direct substitute sizes

If 355/42R18 is unavailable, the closest same-diameter substitutes on the same rim are 345/43R18 and 365/41R18. 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 355/42R18 you can upsize to 365/37R19 (plus-one) to fit a larger wheel without changing the speedometer reading, or downsize to 345/47R17 (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 355/42R18 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 355/42R18

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