Interesting (good) side effect from replacing 12v battery

All,

So, my 12v battery lasted nearly 10 years (and over 120k miles). Bought the car in December of 2006, and I just had to replace it this week. I tried charging with my battery tender, but something must have gone sideways with the battery as once it "went", it went quick. You could really tell it was going since the water storage pump would change pitch when running after car shutoff (and the brake pump would sound funky).

Did the usual, and bought an Optima yellow top. Fit was great. Removed the handle since there wasn't really room (and didn't really need it). Charged it fully before installing, as it showed up with about a 75% SOC.

Anyway, the interesting side effect. For the last few weeks, I've been having a random mild squeak from the left rear driver's side brake (which are drums on my Prius (think all Gen II's were drums). Hadn't had a chance to pull the drum to look, and it wasn't that bad, just a light squeak when I'd stop (only on stopping, not when slowing). Replacing the battery seems to have completely resolved this. I know the brake booster is on the 12V power system, but I really didn't expect this to be related at all. Very odd.

Glad it's gone, and the new battery is great. Just thought I'd share as an interesting story. =)