Section Width635 mm (25.0")
Aspect Ratio14%
Rim Diameter30"
Overall Diameter940 mm (37.0")
Sidewall Height89 mm
Circumference2952 mm
635/14R30 — Buy Tires

Everything to know about the 635/14R30 tire size

Size geometry

A 635/14R30 tire has a 635mm section width and a 14% aspect ratio, mounted on a 30-inch rim. Sidewall height works out to 88.9mm (3.50") and overall outside diameter is 939.8mm (37.00"). At highway speed the tire completes about 339 revolutions per kilometre — your speedometer and odometer were calibrated against this number.

Direct substitute sizes

If 635/14R30 is unavailable, the closest same-diameter substitutes on the same rim are 625/14R30 and 645/14R30. 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 635/14R30 you can upsize to 645/12R31 (plus-one) to fit a larger wheel without changing the speedometer reading, or downsize to 625/16R29 (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 635/14R30 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 635/14R30

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