Audi automobiles typically require a 22-inch-long windshield wiper replacement blade on the driver's side and a 21-inch-long blade on the passenger side. These blades are generally available at auto parts retailers and large retail stores. To determine the correct wiper blade for your model, look in your Audi's owner's manual, or look in the catalogue alongside the wipers at the retailer for your Audi's year and model.
With your Audi's engine running and the car in park, turn on the wipers and let them extend upward. When the wipers are in an upright position on the windshield, turn off the engine. Grasp one wiper arm and gently pull the wiper away from the glass in order to make it easier to complete this job.
Depress the release tab located on the wiper arm, near the point where the wiper blade meets the wiper arm.
Hold the release tab and slide the blade in a downward position until it unlocks from the wiper arm.
Place the new wiper blade assembly onto the pivot point. Slide it up until the retaining clip locks the new blade in place.
Return the wiper arms and new blades to the window surface. Wet the windshield and operate the wipers to make sure they are properly fitted.