- 1). Sit or lean down in front of one of your tires and locate the valve stem, which will be somewhere on the perimeter of the wheel rim, sticking out from the tire.
- 2). Unscrew the valve cap, if one is present, by turning it counterclockwise with your hand.
- 3). Install the replacement valve cap by turning it clockwise onto the valve stem with your hand. Do not use a tool on the cap, as you can easily over-tighten it, which could strip out the valve stem's threads.
- 4). Repeat steps 1 through 3 for the remaining tires on your car or truck.
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