Years ago on another forum, a person I respected greatly for his auto repair knowledge said he always cracked the bleeder and compressed caliper piston as the first step in replacing brake fluid. He said it was good to expel old fluid in the caliper to make sure it was completely flushed. His theory was that if you just open the bleeder you do not get pure plug flow and some old fluid will not get flushed as it sits stagnant in the caliper. This made sense to me and I adopted that practice. It means a lot of extra work so I couple brake fluid flushes with tire rotation and/or routine caliper service. Anyhow, was just wondering what you all think about this. Is it worthwhile to compress clipper pistons to expel old fluid? Thanks.
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