BRAKES SQUEAKING

Some / most after market Brake kits still have that -brake hard - rinse and repeat - recommendation after installing their brake kits.
OEM brakes (at least for Prius) don't use that procedure during dealer brake checks or replacement. That is if the dealer follows the repair manual instructions for the checks or repairs.

 

FWIW, this was a constant problem with my Gen1 Prius. Especially after some wet weather and it sat for a bit I'd get what I called a light scarping noise just on the last bit of slowing down. I wouldn't call it hard braking and sometimes even just the little braking for the last few MPH was good enough if some city driving needed it a half-dozen times or so.

As evidence it is just the brakes not being used, I finally gave away my Gen1 to a nephew at 220,000 miles still with the original brakes! The worst situation I got into was a road trip to Disney World where I left the car parked with the hand brake on for about 10 days of wet FL weather. The brakes got stuck so bad I had to seriously gun the engine to apply enough force to get them un-stuck! They scraped a bit after that, but after a bit of driving and braking all was good again. Lesson learned was next trip I left the foot brake off. Hey, it was Florida, ain't nothing gonna roll anywhere when it is so flat!

I do have the same issue with my PPPXP (Gen5), but at least so far it isn't as bad as it was on the Gen1. Still there for sure, but not as bad.

will

 

I supposed the most divergent opinions need to be the least civil?
From the 2023 Owner's Manual:

 

At 700 miles, the OP car is outside the break in period. The suggestion of some hard braking to clear the brakes of any rust to see if that fixes the noise wasn't a risk.

 

I'd be inclined to just use the brakes, as usual, not doing anything dramatic.

FWIW, anytime I wash our car and put it away for a few days, the next drive there'll be noise from the rotors, for the first few blocks.

 

Little use combined with a gentle braking habit can mean regular brake use isn't doing enough to keep the rotors clear with a hybrid.

The hard braking was recommended to ensure the friction brakes got used.

 

Hard braking and/or acceleration is never good for your car—in the break-in period or not.

Moreover, as I mentioned here, if the noise is being caused by a manufacturing defect, hard braking will only lead to damage to the rotors/pads. That is why I suggested having the brakes checked at the dealer under warranty.

 

In that case, there is nothing to worry about. There is also no need for hard braking as some suggested, which will unnecessarily wear the rotors and pads. If the problem is being caused by winter rust, hard braking everyday to get rid of the rust is like remachining the rotors and pads everyday, which unnecessarily shortens the life of brakes. I would rather have some rust on the rotor surface than wear the rotors and pads out.

This is from a 1985 Corolla FWD repair manual. Read in particular the “note”:

 

LMAO.
Best to not drive the car if you plan on braking or accelerating.

The Gen 5 doesn't have drum brakes...Lol

 

Nobody said that newer Priuses had drum brakes. I happen to own one. The old repair manual is for both disk and drum brakes.

 

If you put the car into Neutral then you can do a long gentle brake as regenerative braking is disabled in Neutral. That's what I do every now and then on a long slow slip road on my way home. Cleans the disks/rotors up a treat .

 

My car was parked for almost two days after the rain storm, and my Gen 4 Prius Prime brakes squealed quite a bit on the rusty rotors for a while. It was gone after driving for several miles when the rust was polished away. I don't remember it ever being that drastic. You don't use the friction brakes much on a Prius, especially if you drive gently like me, and it takes longer for the rust to clear.

 

Try this before you conclude there's anything wrong at all:

It's just part of the Prius experience. I've gotten so I just do it by second nature whenever I notice the brakes noisy, and I hardly even notice myself doing it.

 

Mine does exactly this as well! 2024 AWD LE

 

Oleg and ST
"..the brake pads and discs make a noise as they are slightly pushed"

I would offer to apply the brakes with more force, not just slightly.
The easiest thing you can do, to eliminate a squeak noise, is to re-bed the pads... drive to 75 mph and activate abs (brake as hard as possible) to slow to 45 mph, let cool for a minute and repeat 5 times.

As for the noise...squeal, cluck, or some other noise you both experience?

Regarding the dealership repair, the techs may be on flat-rate and since the brakes (even control arms, shocks, and sway bars) visually appear safe and sound, they "call it a day" so all is okay/ within spec (rotors tight, caliper tight, lug nuts secure, pads thickness okay, etc).

I wouldn't change the pads, yet.
Besides braking harder, I could suggest diving deeper and removing the pads; and on a machinist's flat surface sand the pad to rotor surface level and also bevel the pad's leading edges (what we former racers term blueprinting).
Check the pad to caliper piston surface to ensure the anti-noise padding/ surface is intact and perhaps add some anti-noise material.
Further, make sure all the anti-rattle clips and caliper pins are lubricated... the small metal areas on the pads too.
Lastly, thoroughly de-glaze the rotors with sandpaper/ steel wool and brake cleaner.
That's for a squeak.
If a clunk, get out your torque wrench and check eveyy brake and suspension bolt you can for proper spec.
Further visually insect (even under the hood) for witness marks of shock. suspension movement.
Below the car, ditto, and also visually look at all the rubber bushing, even going as far and using a pry bar to ensure the control arms (and all) are not moving.

If all that fails, sure replace the pads and turn the rotors... a fresh start

Repeating, don't depend on a dealership to do all this I wrote in their inspection. They may find nothing wrong and present you with a 2 hour labor invoice. But if you like to not DIY, ask an independent shop to do the above. Noting the flat machinist surface is very important to utilize. Squeaking brakes are a normal condition for many cars.

Good luck.

 

For sanding the face of brake pads? I recall walking through the service department of Middlegate Honda: they laid a piece of sandpaper on the floor slab and slid the pads back and forth on it a few times.

 

All of that is more elaborate than you typically need for a recurring issue that has been common to all Prii since the first generation. After any time the car has sat long enough in damp conditions, the brakes will be noisy and grabby. That goes away if you just shift into neutral for your next two or three normal, no-drama, ordinary stops.

Nothing more than that is needed. It will get the brakes quiet again, which will last until the next time the car sits a while in damp. Then you can do it again. It's just part of life with a Prius.

You can pursue much more elaborate remedies ... re-bedding the pads ... hard braking from 75 mph ... you name it ... and those might also work ... and will also last until the next time the car sits a while in damp.