I have this squeaky noise at the break pedal.
First I thought is is coming from the footwell but I am convinced now it is in the internal linkage of the booster.
I know others have the same problem but I never saw someone suggesting a solution.
My question: can I pull the vacuum hose and spray Silicon spray into the booster? Does this hurt the booster?

I am desperate and close to changing the booster if there is no way to deal with the old booster.