OEM rotors and pads mediocre

there have been odd reports of all generations with brake problems due to salt. maybe it is strictly personal use conditions, or some are just defective.
on the whole, most have no issue

 

I have replaced the rotors on four of our vehicles so far with zinc plated ones ( PowerStop brand ).

They have been holding up far better than the OEM rotors did...and we are in a high road salt area. Full disclosure that I did this as an 'experiment' on the first vehicle ( 2012 Prius v wagon ). I liked the result so much that I have been swapping the rotors out on the other vehicles when the time comes. For me it's a 'why not' type of thing at this point since I'm in there doing a brake job anyway.

 

I've got around 93K kms, and when putting the snows on I see the front pads are around 6mm still. Maybe punishing amounts of road salt in your area are corroding the rotors, accelerating wear?

Rear pads I had to replace early, and they're currently maybe 8mm. I messed up rear caliper piston orientation first time round.

Rotors all fine.

 

My brakes are still fine at 140K on my 2017. I guestimate my miles are about 60-70% highway. There is a saying that salt is harsh on everything but saltwater and saltwater fish.

 

My parents have a 2014 with at least 80k miles at last check in Chicago, which should have fairly similar road surface salinity to where OP is, and I am fairly certain it's still on the factory brakes. I haven't exactly taken the wheels off and looked at them in person, so not sure what state they are in, other than being functional and the mechanic not telling my dad it's time for new brakes yet.

Although, I'm also not surprised that Toyota maybe used inferior brake components on the Prius as a cost cutting measure. It's not a performance car by any means so quick stops aren't super important (except you know - for safety). Also because in most normal conditions MG2 is doing a good deal of the work, from a durability perspective, even crappier pads and rotors will still (typically) outlive nicer ones on a conventional vehicle.

 

Yep, salt is our Kryptonite! I hate it! I'm originally from Maine and "rust bucket" is what a car becomes in too short a time period!
Do you have any car washes that run in the winter? We have one that has the under-carriage spray and I'll run my cars through it during the winter (when it warms up over freezing) after we've had snowstorms and that seems to help keep the rust down. (They do use salt in Colorado but also add corrosion inhibitors so I don't think we get rust as bad as Maine used to....not sure if Maine is better now or not.)
Anyway, I do all my families brakes and have favorites....Bosch rotors and Import Direct pads (ceramic for cars, semi-metallic for vans and trucks) IMHO I don't think they are much different than the OEMs Toyota uses.

 

do you have and can you share instructions for replacing brakepads?
I'm so thankful with you, all the information that you share is so helpful.

 

I have found that the OE pads are fine. The OE rotors do tend to rust (as we all have discovered) and a rusty rotor will cause the pads to wear as well as make noise when braking. I make it a point to periodically clean the rotor surfaces:

1. Get up to 25-30 MPH with no traffic
2. Put your Prius in neutral so that regenerative braking is disabled.
3. Lightly step on the brakes
4. Repeat as required until the braking smooths out and the noise is diminished.

As our farmer friend noted in an earlier comment, zinc plated rotors resist rust so as to look better, but not on the braking surface as the zinc plating on the braking surface quickly wears away.

JeffD

 

Repair Manual info attached.

 

That's generally the way I do it, too. If I notice that grinding noise as I'm pulling out of the driveway, I'll shift to neutral for the first stop signs out of the neighborhood, and that usually takes care of it. It's pretty much second nature to me now, I'll do it almost without thinking about it, when I hear that noise.

You'll see other members who don't do anything special, and just wait for their normal driving to scrape the rust down. Just takes a little longer that way.

Probably neither way is significantly better than the other; I think I do it my way because I hate my car sounding like a hooptie, so I correct the sound right away.

Either way, scraping the rust off the rotor naturally wears down the pad too. It's probably about the same amount of meat off the pad, whether you follow "shift to neutral and fix right away" or "wait for normal driving to do it".

The one thing I'd say is don't let the rotors stay rusty; if you normally follow "wait for normal driving to do it" but you still hear noise at the end your normal drive, do some neutral stops to make sure it's cleaned up. Leaving the rotors rusty gives the rust a chance to get deeper, and harder, and more abrasive to the pads.

 

If I’ve washed the car and it’s then sat a few days, next drive will have noisy brakes, for the first mile or two. Even without shift to neutral tactic: pretty much every time I touch the brakes.

 

Just a friendly warning, the OE rotors do build up significant rust on the outer edge. When I brought my 2004 Prius in for it's 60k mile maintenance, the technician said that I needed a full brake job. I declined and at 12 years and 288k miles the original pads, rotors, drums and shoes were all still on the car and no problem stopping the car.

JeffD

 

Another thing is that, if not used often enough, the rust that starts at the rotor edges just works its way inward. Eventually you have only a stripe in the middle where braking happens.



The rust at the edges gets well-enough established that the pads can't wipe it off anymore. Instead, it adjusts the shape of the pads to suit itself.




Note in the upper photo that you can see the pad is being eaten from both the top and bottom edges.

The bottom-edge contour isn't visible in the lower photo because its radius doesn't reach out to the side edges yet.

 

Yep that crap on the roads in the winter can do a lot of damage to even quality parts. Here in Colorado, during the winter, whenever we get a warmer day (above freezing), I'll wash my cars and spend extra time spraying down all inside the wheel wells and also the tires and brake areas to wash that stuff off...seems to help a bit in our vehicles.
My wife's 2017 Prius only has 27,000 miles and I checked her front pads during the last tire rotation and, still, has 6mm....so looking good.

 

This very thing just happened to my 2016. It's the rotors that kill the pads. It's the salt that kills the rotors. And make doubly sure you check the inner pads (esp in front) as they are the ones that get the use if the slides freeze up. Get coated rotors if possible, and keep the salt off. No easy fix for that. Ceramic lube the slides every 30-60K if used in salted areas. Thankfully, my pistons weren't seized, but the slides were certainly dry and "stuck" enough not to do their job.

Tip: The rear pistons need a special tool to turn the piston in and I had to use silicone spray to avoid the rubber boot being torn as the piston turned. Too much corrosion equals sticking rubber parts. I will be coating the underside of my Prius for winter with Fluid Film to save the frame and hardware.

 

I do a quick inspection with every tire rotation. It includes wiggling the calipers in and out on their slides. Done frequently enough, as with tire rotations, that's easy to do. You will feel that the existing slide grease got a little peanut-buttery, but it wakes right back up with just a few strokes in and out. (Keep in mind that in their normal life, they aren't moving more than a third of a mm in either direction.)

Just keeping up with that, I hardly ever have any need to further disassemble or regrease anything. (On the rare occasion when that's needed, it's worth knowing that Toyota does not specify any silicone grease for that use. their spec is a glycol grease with lithium soap thickener. 08887-01206 to buy a whole tube, but you don't have to if you buy a caliper rebuild rubber kit; it comes with a little packet of the right grease.)

Don't overlook other parts besides the slide pins. The fitting kit (springy clips that insert in the caliper mount and hold the pad ears) can need attention too. Those don't take grease (it would only hold dust and grit), but they come with a dry Teflon-like coating when new, and it can wear off, and later they can rust, and that also keeps the pads from releasing. A new fitting kit is quite inexpensive.