I was changing the brakes on my brother's yaris, because he insisted they were grinding, yet the exterior brake pads still looked new. After pulling everything apart, I realized the pads had worn extremely unevenly, to the point where the inside pad had absolutely no pad left (not a figure of speech, there was just metal) while the outside pads still had at least 75% of life in them. This was the same on both sides, and both rotors also had to be replaced because of how badly grooved they had become because of this. The issue is that one of the guide pins on both sides has a plastic ring near the tip, and for some reason this causes pretty bad grime to get in (not sure how, just noticed a correlation between these plastic tips and brakes seizing after changing brakes on 6 different cars and consulting with an uncle who also does a lot of brake changes on his family's cars) This caused the guide pins to be rusted pretty bad all along the first 1/2", which prevented them from doing their job. I only had pads and rotors on hand and was unable to order guide pins before the car had to go, so I had to clean the rust out, which took at least 45 minutes for each of these pins since I only have metal brushes for this type of work. Better fixes would include replacing these pins, replacing their rubber seals (although these still looked in pretty good shape) or replacing the caliper bracket none of which I have tried yet. Preventive maintenance would be to open these up fairly regularly to clean and regrease them.
I would've thought this was just a bad car, however my uncle, who also owns a yaris from around the same year IIRC and stores it in a garage every night, had the exact same uneven brake wear when I opened it up, and although his guide pins weren't rusted, they were still pretty full of gunk.
A D V E R T I S E M E N T S
I was changing the brakes on my brother's yaris, because he insisted they were grinding, yet the exterior brake pads still looked new. After pulling everything apart, I realized the pads had worn extremely unevenly, to the point where the inside pad had absolutely no pad left (not a figure of speech, there was just metal) while the outside pads still had at least 75% of life in them. This was the same on both sides, and both rotors also had to be replaced because of how badly grooved they had become because of this. The issue is that one of the guide pins on both sides has a plastic ring near the tip, and for some reason this causes pretty bad grime to get in (not sure how, just noticed a correlation between these plastic tips and brakes seizing after changing brakes on 6 different cars and consulting with an uncle who also does a lot of brake changes on his family's cars) This caused the guide pins to be rusted pretty bad all along the first 1/2", which prevented them from doing their job. I only had pads and rotors on hand and was unable to order guide pins before the car had to go, so I had to clean the rust out, which took at least 45 minutes for each of these pins since I only have metal brushes for this type of work. Better fixes would include replacing these pins, replacing their rubber seals (although these still looked in pretty good shape) or replacing the caliper bracket none of which I have tried yet. Preventive maintenance would be to open these up fairly regularly to clean and regrease them.
I would've thought this was just a bad car, however my uncle, who also owns a yaris from around the same year IIRC and stores it in a garage every night, had the exact same uneven brake wear when I opened it up, and although his guide pins weren't rusted, they were still pretty full of gunk.
- Jérémie L., Gatineau, QC, Canada