- 1). Pull the cover off of the nut at the bottom of the windshield wiper arm, if applicable. This nut holds the arm onto the car and is located at at the bottom of the arm. Depending on the type and age of your vehicle, there might not be a cover on the nut.
- 2). Use an open-ended wrench to remove the nut from the spline drive.
- 3). Pull the wiper arm to a vertical position, then pull it toward the front of the vehicle. The wiper should come off with very little effort.
- 4). Use the utility knife to scrape the aluminum from between the grooves in the spline. Use the wire brush to clean the dust from the spline.
- 5). Place the wiper blade back onto the spline. Replace and tighten the nut. Replace the cover if there was one.
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