Brakes Squeal

Could you please tell me how that works?
Certainly, here is a description of how I bed brakes. I posted this in another thread related to this brake noise issue.
Something to consider is “bedding in” your brake pads. Most mechanics do this when they install new brakes. I’ve done quite a few brake jobs on my cars everything from Porsches to Diesel Trucks. When I bed in brakes I did it by finding an empty long road with no traffic. This requires a road with no stop signs or traffic lights or other cars on the road. It’s the process of getting your vehicle to about 60mph and applying the brakes hard but letting off before you come to a complete stop. The goal is to brake hard until you slow down to about 10 mph. Keep rolling do not stop completely. Then immediately accelerate up to 60mph and do it again and again. After doing this six or seven times in row the brakes will heat up quite a bit. It will transfer brake pad material to the rotors and rotor material onto the pads. After six or seven consecutive hard applications of the brakes like this you want to let them cool off. Drive and let them cool for a bit before coming to a complete stop. Remember this requires a road with no stop signs or traffic lights or other cars on the road. Stopping and holding the brakes while they are this hot (try not to do it) can transfer too much pad material to the rotor in one spot and can cause vibrations later. I hope I explained that correctly.

After writing that post I learned a whole lot more about brakes from reading posts (in this thread) by forum member Belisarius. I would recommend reading his posts (very informative).

Just for a reference:
Here is a link to the related thread I copied my “bedding brakes” process from.

Post in thread 'NHTSA report a problem'
NHTSA report a problem
 
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I did something similar, but not the same.

The brakes on my 2024 FE were squealing in reverse big time. They were still squealing after 6K miles.

Two weeks ago I went on a road trip to New Hampshire. While I was there I drove up Mt. Washington (8 miles uphill). Coming back down there is a big problem of people's brakes heating up - so much so that they have pull-offs every 100 yards or so where people need to pull over and let their breaks cool down!

After driving down and having to stop 4-5 times just to let my breaks cool - I have not heard a single squeak since!
 
Does anyone else exerience brakes squeel in reverse? Mine seems to do it mostly after it has sat for a while. I only notice it in reverse.
Hello looks like most LC s do it world wide !!! mine is also squeeling bad in reverse when been sat for a while i,m in the UK
 
Mine definitely squeals 1st time reversing after being parked overnight. I've found 2 very easy solutions that both work for me.
Option 1 back in to parking spot at night.
Option 2 don't use brakes when backing up 1st time, in reverse my truck only moves at 2 mph so it's easy to back up 30 feet without using the brakes and if I need to stop the squeal is very brief.
I'm not suggesting that it isn't a problem, just that I am able to avoid hearing it most of the time.
 
I wonder if this is happening because the breaks are not used as rigorously thanks to regenerative breaking, which causes surface rust to form on them. This, at least, is a known issue for EVs.

I believe regenerative breaking is not used in reverse, so this may be the reason why the noise mainly occurs while breaking in reverse.
 
It has nothing to do with hybrid breaking as many of the local owners here in the middle east are reporting the same issue with the non-hybrid petrol and diesel variant of the same car.
Indeed, my key suspects are bedding, ability to bed in, brake bias, brake pad rotor quality etc. I wish anyone here posting post service tells us what or how do the pads look like. Do they have shims? And, if folks tried everything, bedding, loaded car bedding etc, we may have to concede that the combination of rotors, pads and brake bias settings induce this frequency. Personally, if this bugged me, I would try an aftermarket higher quality rear rotor set, or pads to start with. However, if the piston pressure is too light, you can glaze or squeal almost any rotor in the universe. I am curious what LC owners with a load, get when backing up. I would suspect a higher piston force and less squealing.
 
I wonder if this is happening because the breaks are not used as rigorously thanks to regenerative breaking, which causes surface rust to form on them. This, at least, is a known issue for EVs.

I believe regenerative breaking is not used in reverse, so this may be the reason why the noise mainly occurs while breaking in reverse.
I heard and read firsthand accounts of tesla owners hit with 8,000 USD bills as their regen ruined rotors and seized one or two pistons. 4 rotors + 2 new callipers, the bill gets ugly. So regen braking never causes rust, it is moisture and oxidization, and yes, this occurs if regen braking has the owner NOT using brakes. Canadian Tesla owners I know, tell me changing the bias Braking vs regen. Because what also happens it when you DO need emergency braking, unused glazed or unbedded rotors, on cold asphalt just double your braking distance on a 5500 lbs or heavier sedan. The rotor capacity to absorb energy is fractional. So if you are a heavy EV owner, never touch or use the brakes to let the mass heat them up, frankly, you are begging for stupid bills. May save some kw/hr but thousands of dollars in repair bills and CO2 manufacturing steel rotors nullifies everything.
 
At first, it used to only be first thing in the morning. Now, it’s always after I get home from work, which is about a 5-20 min drive. Although, it seems to be less loud since I took a short road trip (about 409 miles rt). I was driving a bit more aggressively, this braking more aggressively. 🤭
 
I finally had a squeal in reverse and I think I know why it happened to me. I usually garage the LC and I left it out on a high fog night. I'm pretty sure it was due to condensation on the brake parts. It only happened once in 5k miles and has never happened again.

For those of you where this has happened consistently do you park outside?
 
I finally had a squeal in reverse and I think I know why it happened to me. I usually garage the LC and I left it out on a high fog night. I'm pretty sure it was due to condensation on the brake parts. It only happened once in 5k miles and has never happened again.

For those of you where this has happened consistently do you park outside?
Inside, outside...
Doesn't matter.
Granted its PNW in the fall, so there's plenty of condensation/moisture.
 
I finally had a squeal in reverse and I think I know why it happened to me. I usually garage the LC and I left it out on a high fog night. I'm pretty sure it was due to condensation on the brake parts. It only happened once in 5k miles and has never happened again.

For those of you where this has happened consistently do you park outside?
Doesn’t matter if it’s park inside our outside the garage. I’ve even had it when it was sunny and dry and had been driven a while.
 
Check out Lexus GX 550 Service Bulletin, L-SB-0036-24
Replacing front Rotors, Pads, anti rattle kit and adding an anti squeal “Shim Kit”. All are new part numbers. I have my GX scheduled for next week.
 
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