The wiper assembly on my car has some play. If I put lithium grease once in a while, it works fine. If I don't put grease or oil, it jumps on the screen. The car is 27 years old and I like it.
Just keep greasing it. As long as it’s working, just keep greasing the thing. It’s going to be hard to find good parts for something that old anyways, and they are going to be expensive. Just keep greasing it and see how long it will last. Lithium grease is good stuff. If you want to see if there are any better alternatives, a technician from YourMechanic can inspect your wiper system and, if needed, can source a wiper assembly and install it for you.
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