Brakes wearing unevenly

The left brake caliper is sticking which caused excessive brake pad wear.

 

Patrick has given you the major reason y that happens.

 

The left side is down to the wear squeelers. There to alert you theirs no more pad left.

Whoever replaced the pads never greased the slide pins. Your looking at new rotors too or maybe enough meat left to get them cut..

 

Check the caliper slide pins, these are what allow the caliper to move freely laterally. They need periodic relube, and verfication the sealing boots are still pliable, doing their job. Sil-Glyde Brake Lubricant is one product suitable for relube. It has the appearance of vaseline or silicone dielectric compound.

When the pads are out you can verify caliper slide pins are still working as they should, by just gently shifting the caliper side-to-side: it should move fairly freely. If it doesn't you'll get uneven wear, drag.

 

..and the major reason y the pins gets sticky in there, is because of corrosion that has developed overtime, from unreplaced brake fluid. Brake fluids are hygroscopic (absorbs moisture from the environment).

Ensure you get a brake flush done on the car before replacing another sets of pads/rotors. Not having a flush done to take care of any moisture in the brake system would compromise the slide pins again in future.

Ensure the slide pin boots are inspected for failure. A torn boot, would allow the introduction of water/ice in the path of the pin(s).


PS: Have also experienced some I stances where the caliper pistons get stucked. Reason? Corrosion in there.

Dxat

 

I don't think the brake fluid has anything to do with the corroding slide pins. Fluid never touches the pins.

They corrode from lack of lube and extreme heat. Extreme heat creates lack of lube lol.

I had a front caliper get stuck on one of my Crown Vics I had just bought. Rolling down the road I smelled something burning and the car started pulling to the left hard all of a sudden. I knew exactly what it was too lol. By the time I pulled over which was quick the tire was smoking.

No extinguisher in the car it would have burned to the ground. In a big car its no joke when a caliper gets stuck. Very exciting.

Autoway in Florida will not flush the brake fluid. I asked for it they turned me down.They were seeing too many ABS failures. None of the dealers in there network flush g2 brake fluid. Oh they'll drill the sh*t out of you for a brake job but wont flush it.

 

You were very lucky. But y would they shy from a brake flush? Maybe they just scared flushing a Prius or what?

Like I did say in my post above, asides the caliper pins getting stuck, the caliper pistons too sometimes get stuck because of ruptured piston boot that hasn't being noticed. What do you think about that?

 

They say the flushing damages the ABS module. The service advisor I talked to at this very big dealer knew about all the Prius issues. They see alot of Prius.

 

It's not worth cutting rotors, I would replace them with new ones and if the caliper doesn't retract easily replace it and the hose.. You have a lot of miles on it and these things don't last forever. I always replace the hose with the caliper after getting burn too many times in the past.

 

They must be scared.
Brake flushing on the Prius, or hybrid cars have got procedures. They may just not have that time, but it sure has being done.

So, what happens if your car, for instance, has got lots of mileages on it, and the fluid in there has stayed more than 2-3 years? Take the car to another dealership that understands that there's a need to flush, or just drive em until the brake components develop some fault?

 

I have this problem too (uneven brake pad wear). I noticed it when I switched to my winter tires. I'm at 90k and will probably have to put new pads on in the next 20k. Here's a short video on how to fix:

I will say the two times I changed brake pads on other cars, there was always at least a little bit of difference between the two sides. On a Prius this means your brakes might only last 100k instead of 120 or 150k . Granted, I've never owned a car with less than 60k and probably never will. Seems inevitable on an older car that the slide pins loose their lubrication and get corroded, especially when on a Prius where they might only get new lubrication every 100 or 150k.

Looking at the pics, it looks like your left rotors are damaged from the brake pads wearing off and metal on metal contact. However your right rotors look okay from the image. In most cases you'd want to replace the rotors as a pair, so you may well need a new set.

 

Toyota USA says to do brake service every 3 years or 30K miles. That would include pin lube.

 

That's what I'm saying too!

 

Mendel, interesting that you mention this, considering you posted this previously: Prius brake service recommendation - from a Toyota service manager | PriusChat

I agree a service every 30k is ideal, but considering a set of pads is only ~$30, it's hard to justify. I just inspect the brakes yearly when switching out winter tires.

 

It's not ideal, just spec.

 

My car is 10 years old never touched the brakes or fluid.

 

And you're proud of that?

 

For Prius, I would not worry about brake fluid replacement until the brake actuator assembly is replaced.

 

Why? Old brake fluid can cause your calibers and wheel cylinders to leak and/or not return and some other problems as well. Changing the brake actuator won’t fix those.