Section Width395 mm (15.6")
Aspect Ratio45%
Rim Diameter18"
Overall Diameter813 mm (32.0")
Sidewall Height178 mm
Circumference2553 mm
395/45R18 — Buy Tires

Everything to know about the 395/45R18 tire size

Size geometry

A 395/45R18 tire has a 395mm section width and a 45% aspect ratio, mounted on a 18-inch rim. Sidewall height works out to 177.8mm (7.00") and overall outside diameter is 812.7mm (32.00"). At highway speed the tire completes about 392 revolutions per kilometre — your speedometer and odometer were calibrated against this number.

Direct substitute sizes

If 395/45R18 is unavailable, the closest same-diameter substitutes on the same rim are 385/46R18 and 405/44R18. 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 395/45R18 you can upsize to 405/41R19 (plus-one) to fit a larger wheel without changing the speedometer reading, or downsize to 385/49R17 (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 395/45R18 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 395/45R18

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