Others have commented on Prius Prime brakes developing pulsing and wear sooner than expected. This seems like a pretty extreme case (Please, see photos) Months ago, our 2017 Prime (Advanced) started having brake noise similar to, but more persistent than what typically results from superficial rust due to lack of use. The sound didn't go away entirely, even after long down-hill scrubbings with the car in neutral and gentle application of the brakes. To deal with this, we had the back brakes cleaned and lubricated by Della Toyota, Plattsburgh, as they suggested. However, a faint noise persisted from the front, so I eventually took it back to have the same thing done to the front ones. This time, the service rep said that his boss told him that it had been a mistake to approach the problem that way in the back to begin with. All the pads were too thin and the rotors scored. They had to be replaced on all four wheels! I was skeptical because the car only had 35k on it, and I expect to get at least 100k out of a set of brakes. A second opinion came from the Monroe guy who changed out the snows and did the NYS inspection in April. He said the brakes were fine, just a little rust on the back ones. I have been going on that confirmation of my own experience since then, but the noise has gotten steadily louder, which is especially repulsive on the quiet, electric car, so yesterday I decided to drift it down a steep hill and try an emergency stop. That uncharacteristic stomp on the brakes at about 35 mph caused a loud grinding, crunching noise, and there was what looked like a little puff of something bright coming from the left front of the car. I tried it again-- same thing, but worse. Same a third time. Could that be a small cloud of metal filings? We are about to launch on a one-day trip covering hundreds of miles on the interstate. Images of having to stop fast and not being able to suddenly became overwhelming. I took the car to DARCARS of Frederick, MD, on Rt.85. According to the service rep, delamination of and corrosion on the surface of the rotors created a unique, sandpaper like texture that has gobbled up the pads at only 36k. *The assembly that holds the pad on the inboard caliper of the LF wheel was eroding away!* Reporedly, this is so bad that it was in danger of getting down to the piston, which would have resulted in a catastrophic failure due to loss of brake fluid. Our 2017 Prime is unsafe at any speed! The combination of the coarse texture of the rotors and the resulting wear on the pads on this Gen V is unique in the experience of this large dealership. The service rep. concurred with my opinion that it should go at least 100k before needing brake work. The rear pads were down to 2-3 mm with negative (?) mm on the LF inboard caliper! Once again, the mechanics in this large facility say they have never seen a case like this in a car with so little mileage. We are a Prius family since 2005 and always drive for good mileage. We charge the car from our own solar array and know that every time we use the brakes, we are wasting valuable energy. This sounds to me like a possible metallurgical failure in the rotors, but, according to the dealership, there is no record of a tech bulletin to that effect, yet. We narrowly avoided disaster by taking it in for assessment before launching on a one day, 600 mile drive on the interstate. It is on the lift awaiting parts to arrive this Tuesday. I am very curious to hear what people think about this case. We have to make a decision about how best to deal with it by tomorrow morning! Comments are welcome!
A Gen V?? What's that? Anyway, it looks like some stuff is fine and other stuff is super corroded. This looks like something that should be covered by warranty. You have parts that look like they've been soaked in sulfuric acid bolted to parts that look almost new.
Sorry, folks, I thought that Prius Primes were Gen V! I will change that. (What generation is a Prius Prime, by the way?)
Exactly! We are out of warranty. The 2017 was the first model year, so I bought the extended warranty. However, as the Della staff explained, pads and rotors are not covered by either of those arrangements!
That is correct. I don't have either the car or the log so I can't give exact figures, but I think it still doesn't have quite 38,000 miles on it. The attached pics were taken yesterday at the dealership.
Was this car flooded at some point? Torch the brakes going down a mountain? Not that either would fully account for the situation, just trying to make sense of this. It's such a weird presentation of conditions.
Prius Prime is sometimes called a 2nd generation plug-in. It is based on the 4th generation just as the PiP was based on the 3rd generation. Same engine, frame, etc as Gen 4. Just has some minor styling tweaks, bigger traction battery (of course), and a sprague clutch between the engine & transaxle that lets it go faster in EV and use both MGs rather than just MG2 to power the wheels. Everyone I know just calls it the Prime, but that's going to have to change now that Toyota has released the RAV4 Prime.
Hmmmm. Interesting. A couple of things..... 1. THIS is one of the (many) reasons that I NEVER recommend an OEM extended warranty. If you have a wobbler (as this case is) sometimes you have to hold the dealer's feet to the fire to get them to cover a repair. Toyota is usually better about fessing up when they mess up IN THIS AREA and there might be some indication that they have this time. UNFORTUNATELY you're seeing other people....and having the repair done at DARCARS of Frederick, MD, on Rt.85 might have been unwise. First thing I would do is review your records and the warranty and maintenance guide.....because this MAY not have been caused by abuse or neglect. other than living at or near 44 degrees North by 73 degrees...presumably West. You didn't say, and no...that's not me being a typical westerner. If you lived near 44 degrees north by 73 degrees east you would need a much different form of transportation. The second thing I would do is VERIFY that you have an OEM extended warranty and then review all of the mice type in this document. I do not consider rotors and hardware to be a "wear" item and my finely honed Spidey senses tell me that either you're being under-served by your stealership, or DARCARS of Frederick, MD, on Rt.85 is soaping you down a little or both. Make sure you keep all of the parts because if you've been following the maintenance guide precisely enough to satisfy your end of the warranty then thing number third might be to dump all of those parts at your stelaership and demand an accounting. This might also be an NTSB beef - although I sorta doubt it. Your latitude and longitude suggest that you live either in New England or Moiynkum District, Kazakhstan. Not judging...but the former has lotsa retired folks driving Primes...or G4 Priuses.....which is pretty much the same car and probably uses pretty much the same brakes. They do weird and interesting things up in the frozen north such as using salt and sand on their roads. Again....not judging but I think that your dealership MIGHT have contributed to the early demise of your brakes. THAT's not an NTSB beef....it's a dealership error or problem. Good Luck!
A technical request to the OP: could you revise your location (in Avatar), to something a little more colloquial? I mean, this is not a Breaking Bad Blueray Barrel Easter Egg; it's Priuschat, lol. I was wondering if you're in some rust-belt region, looked at the avatar, and oh yeah...
The only hard part is the profile field cuts off the length before you can see if the longitude is east or west. But given one of the choices is in the US and the other is in Kazakhstan, I have my guess. Google Maps Google Maps Rotor rust seems to be affected by how often the car is driven. When it's there a short time, it is easily scrubbed off and the pads can remove it when the car is next driven. If it sits there longer, it becomes entrenched and abrasive and eats the pads instead. Happened to my Gen 1. Perhaps significantly, for a lot of the time I had the Gen 1 I was bicycle commuting and not driving it much. My Gen 3 has been driven more often and the rotors have stayed quite clean, but I have a bit of a bad feeling what I will find in my first post-Covid inspection. I once looked at some brakes on a friend's SUV and saw that one pad was down to the metal, and said "you definitely need to order pads and a rotor, but you may as well drive (sparingly) until they come in, as you've already trashed the old ones anyway." It seems it only took a couple days to further wear the pad backing plate thin enough that it got folded in half and thrown out of the caliper, leaving the piston to touch the rotor directly, and get cocked slantwise in the bore, so the job turned into rotor, pads, and caliper. I had never seen that happen before.
All I can imagine is that your roads--sorry, I cannot divine your location--get treated with a corrosive compound during winter and it stays on your wheels for extended periods. I would get complete set of rotors and pads and try as best I could to rinse off the road salt from the wheels as often as possible during the winter months. I don't see any case for a warranty claim--nothing is defective, just extensive corrosion due to road treatment. If you do get new brakes, pay attention to the break-in period. Don't be in a hurry to take off on your 600 mile road trip until the new brakes are bedded-in.
+1 That amount of corrosion is incredible to me. Here's a current pic of my 7 year old C-Max original brakes; zero service or maintenance (not proud of that last fact).
Assuming this is all due to road salt in upstate NY area, here are what my 2017 PRIME rotors and brakes looked like last fall. That is after 2 full winters and 36kmiles on NE roads just as bad as your roads are in terms of road salt. Yeah, road salt corrodes, but not as bad so fast as I am seeing on your car. Given time, I am sure mine would have looked just yours, but I hope it takes more than 3 winters. Just curious, if your dealer is in upstate NY, Della Toyota, Plattsburgh, NY, why did you take your care to DARCARS of Frederick, MD? I would be interested to know how much the entire job cost, for I will be doing that at some point in future, hopefully much later than your car, but I know it is inevitable. If my other Toyota is any indication, anywhere 7-8 years, 70-80kmiles is when I needed whole brake/rotor jobs.
Have you done an emergency stop in this car before? the ABS system makes strange sounds compared to other cars I've driven. It's not a low frequency pulsing, but more of a grinding noise. But a cloud of dust is not normal. Older Toyotas often get stuck pistons in the brake calipers. Lubricating the slide pins won't fix it, the calipers need to be rebuilt or replaced. It would be unusual for it to happen so quickly, but maybe you got extremely unlucky? A stuck piston makes the brake pads drag, wear away quickly, and sometimes overheat.
