The wiper shaft(s) must be fitted with rubber, as must the wiper motor, to avoid vibration as much as possible.
In addition, the wiper shaft grommets have two more important functions: they create a sealed assembly and protect the paintwork.
On some models and/or years of manufacture, the grommets consist of two parts, the part with the elevation is mounted from the inside and the other part from the outside.
Worn gaskets let humidity pass through, if there are cracks in the rubber, don't wait to replace them.
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