When I press and hold the brake and lightly release the pressure. The brakes would make this loud squeal. This happens when the car on or off. Just found out today that if I have to stop really suddenly, it makes the same noise. I have an rx450h w 42k miles. Any thought?

 

a lot of makes and model produce similar noise. It is not a safetry issue. at 42K miles you may want to check your brakes for wear...

 

Brakes are 8 and 9. I just purchased the car and it was a certified. The noise is not not quiet. My wife can hear it inside the house when I'm trying to determine the issue.

 

I have same problem with my CPO 2011 RX 350. Showed to dealer and he sad it is normal for brakes, they are making sound when starting to wear because they are moving
Same 8 on all pads.

 

You could have glazed rotors and pads and a simple servicing to remove the glaze with a little sandpaper and then cleaning and greasing the brake hardware could remove the noise. This is not the type of service that the dealer likes to do as it is relatively inexpensive and almost pure labor. Try to find a good independent shop.

 

I brought my car to a Toyota dealership, they are saying something about the booster. They can't start to work on it since they can't claim Lexus warranty. I will have to wait since Lexus is about 2 hours away.

 

That makes sense since you said it made the same noise whether the car was on or off. It probably has a leak and that is making the noise. They are expensive, especially since you have a hybrid wherein the brakes are really complicated, so it is nice to have the warranty.

 

Are your ebrakes on? lol - I know I left my ebrake on once and it did that. scared the s*** outa me.

 

On my 2010 RX450h with 50,000+ miles , I had a "seal barking" noise when I pressed hard on the brake pedal. The noise was caused by the brake actuator (a $2500+ part), which was replaced under the extended warranty. The same brake actuator problem also occurs on many Prius models from 2003+ for which there is a TSB.

 

the ebrake was never engage during the time I pressed on brake. Dadcat, that sound similar to what I have. Do you get that sound while the car is running or not?

 

I think the noise happened both with and without the engine running.

 

great, then that sound exactly like what I have. I will tel the adviser to check that out.