Per Vermont DMV regulations auto technicians have to reject a car which has more than 1/2 inch of rust on the rotors. SO... After just 16,000 miles (after last brake job at 25,400 by dealer!!!) I just had to have front brakes done again. I saw the rotors after they were taken off and there were definitely areas where the brake pads hadn't been fully contacting the rotors, which would have been essentially 'scrubbing' them nice and shiny. Dave said, "5 years ago I would have said 'we may have to do a brake job in a year,' and before that I would have said 'go ahead and drive it and we'll keep an eye on them.' " Dang! I've been taking my cars to this shop for over 25 years, and trust him completely, though I wish he could have bent the rules a bit on this one. My habit has been to anticipate stops, let off the gas, and smoothly apply brake pressure, which always does the job with little effort. Little did I know that because of my 'light touch' I was creating areas on the rotors that weren't getting well 'scrubbed' by the pads... Dave's advice, "periodically head out to the highway, get up to speed, and do some hard braking." Now I'm putting a sticker on my dash saying, "brake like you mean it!" Hope this post helps others avoid the same issue.
I just do the "Prius brake scrape dance", whenever it's needed. If you start with nice smooth rotors, you learn what the brakes sound like with those (nice, smooth, and quiet). Then you can hear it right away when the brakes need the scrape dance. I can usually notice it first thing in the morning, if the car sat overnight and it rained. You just hear the rough scraping sound when the brakes apply. Then all I do is shift to Neutral for my next two or three normal stops. In Neutral, the transaxle can't be used to slow regeneratively, so the brakes have to do all the work. Two or three normal stops like that is usually enough, and you will hear the brakes being smooth and quiet again. It doesn't have to be any kind of production number. You don't have to go extra fast or brake extra hard. I generally do it in such a way that if I had passengers, who weren't watching my hand to see the shift to Neutral, they wouldn't notice me doing anything special.
+1 to ChapmanF. I get noticeable rust buildup on my Gen2 after sitting for the weekend. Gotta do a "neutral scrub off" a couple times a week. Even then, in the salt belt it's only a matter of time before the rotors rust up again. Posted via the PriusChat mobile app.
