Lucked out: the bolt can be broken right off. Or the wiper arm from the motor can break. One of my very first repairs was that I noticed one wiper had a "stutter" where it would stop in a repeated way with a clunk : the wiper arm was broken but was jammed in such a way it still worked-ish.

Rather than replace I cut a 6" piece of angle iron and made a splint. That was nearly 4 years and 50,000 miles ago.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)