Hope for any expert advice with braking problem on 2009 SC430!

I have had recurring issues with braking when driving downhill at speed above 40 kmh, above 110 kmh on flat roads or when braking strongly. The car would make lots of braking noise and the brakes would block/lock!

I had the disks and pads changed twice.
I also had the suspension checked, the geometry alignment redone as unusual wear on the outside of the tires which have been changed as well!

3 garages no solution!!! No easy access to Lexus dealer (French countryside)…

 

Hello,

How did the issue first begin, was the car Serviced at that time, or the problem just appeared out of nowhere?

The wheels would literally Lock Up as if the car is not equipped with ABS?
What kind of Noise are you referring to, is it Scraping, Whining, Grinding, or otherwise?
Do you know at least the approximate area of where the Noise is coming from, or is it going from all around?

So does the issue show up differently if you are going Downhill instead of driving on the Flat Road?
In that case, does the issue feel the same when you are going Downhill at 40km/h as it is when you are going on Flat Road at 110km/h?

What Brand of Parts did you use for the replacement?
Did you use the same Brand or a Different one for the Second Replacement?
Did the Old Parts, before any replacement, show any unusual Wear or other issues?

When the car was at those 3 different Garages, what did Mechanics there say, if anything at all?

It is pretty hard to make anything out of what the issue actually is, a Video of the Noise and the "Lock-Up" would be quite helpful. Your car is equipped with a Hydraulic Booster, it is not a usual setup if compared to regular cars, which does complicate things further, especially if that system was never checked or serviced properly, as they are known for some issues, at least their earlier revisions.

For now, if the issue is that severe, try to avoid driving the car on the Main Roads until there is at least some clarity..