The front brake pads fell apart on my 01 Prius with 86,000 miles. These were the original pads and normally that is a lot of miles for brake pads, but no so a Prius they should last up to lifetime. The inner pads (both sides simultaneously) completely fell apart in a short amount of time while the outer pads still had 1/4 inch pad left. The caliper pistons still seemed to move freely as did the slides. Mystery? Anybody have this problem?
We have seen this on many vehicles coming out of states that use a lot of road salts. It is called delamination within the brake industry. We very seldom replace Prius pads unless there are signs of this happening because they seldom wear out.
Follow up. I changed out the front brake pads with Dura Last pads and had the rotors turned. I verified free movement of the calipers and pads. I saw nothing to determine why the inner pads deteriorated. Since then, it has been 32K miles and no issues - the pads look great. Perhaps hybriddriveguy's explanation applies here.
Mine still had plenty of pad left too when I got my 02 prius. The previous owner had replaced them 4 years ago but due to rust they separated from the backing plate. SO I figure they will need to be replaced every 4 years due to rust causing them to separate.
My front pad fell apart on driver's side only, in a 2002 with 43,561 miles. Due to the dishonesty of dealership where service done, parts and information that I was promised I would receive before the car was towed there, were not obtainable when I went to pick up the "repaired" car. I started a post about it: http://priuschat.com/forums/generat...4-brake-pad-fell-apart-2002-43-561-miles.html My take on the matter is that they were eager to have the car towed there so that they could collude with Toyota on covering up manufacturing defects. Toyota has plenty of lawsuits related to brakes already. Brake pads that fall apart have already destroyed a significant amount of evidence, or left it where most people cannot find it!