1990 Mercedes-Benz 300SEL Windshield Wiper Arm Replacement Cost

The windshield wiper arms hold the wipers in the correct position through the entire range of motion, and are geared on one end to accept the motor that drives the wipers. The other end has one of several clip designs, and the windshield wiper arm will attach firmly into this clip so that it sits between the windshield wiper arm and the windshield.

When the windshield wipers are activated, the switch sends a signal through the fuse, and possibly a relay, and power reaches the windshield wiper motors from one of two paths. When it reaches the windshield wiper motor, the motor will being moving back and forth as quickly as the driver has selected. When the wiper motor turns, the wiper arms, which are connected to the motor, and contain the wiper blades, move across the windshield causing the wiper blades to drag liquid off the glass.

Windshield wiper arms will be replaced mainly for aesthetic reasons or damage. If the windshield arms become bent or rusted, the windshield wipers may not contact the windshield at the proper angle, or there may be no contact at all. Also, the sun will take a toll on these parts after years of use, and fading or clear coat peeling will result, not to mention rust.

Driving without windshield cleaning components is not typically considered unsafe, but there will be no system to properly clean your field of vision if the need arises. If the windshield cleaning system is heavily relied upon in your location, consider repairing the system sooner than later. Also, this system works together to clean and protect the windshield When one component fails, the risk of damage to the windshield is elevated. Lack of lubrication, incorrect windshield wiper angle, and worn windshield wiper blades are all causes of streaking, grooving, and scratching the path of the windshield wipers into the windshield.

As noted, the only reason to replace a windshield wiper arm is for damage to the color finish or physical damage to the windshield wiper arm causing contact issues between the windshield wiper blade and the windshield.

Any signs of damage, failed inspection if factory scheduled maintenance lists the windshield wiper arms, and sun spotting are the major causes of diagnosing the wiper arms as deficient. If the windshield wiper arm fails to hold the windshield wiper blade, fails to engage the windshield wiper arm drive gear, or cannot be folded down for smooth contact of the windshield, these would all call for replacement of the windshield wiper arm.

The old wiper arm is removed from the geared, articulating linkage at the base of the windshield. One per windshield wiper. There are a multitude of fasteners and means of retaining the windshield wiper arms, so the correct tools must be used to remove them. Once removed, the wiper arms will slide off, and the new will slide on. If the windshield wiper arm will not slide off, and since heat should not be used in the area, the wiper arm may be removed with a gear puller.

Some windshield wiper arms may be from the same manufacturer, look the same, have the same dimensions, and same functionality, but when attempting to install, the pattern does not match where the wiper arm connects to the vehicle. When purchasing parts for a DIY replacement, have the old part with you to ensure you are purchasing the correct part number, and the correct part is being given to you.

When replacing a wiper arm, a non-OEM wiper arm will most likely look different than the OEM wiper arm. Avoiding this issue requires replacing both wiper arms with one brand, or replacing the defective wiper arm with a genuine OEM part. If the appearance of the vehicle is of no consequence, this information can be disregarded so long as the wiper arms do not contact one another in their normal range of motion and cause the wiper blades to work effectively.

Windshield wiper arms are a good DIY when they are accessible, but some vehicles require the removal of aesthetic trim panels. As long as the trim panels are carefully removed and installed, and the wiper arms are aligned correctly on the mount, the repair is done easily.