Swapped Discs/Rotors now having a grinding noise, as per title Options

[Tuga2112]

Hi All,

If this is not my first post, it will be the first in a few years, Recently bought my Second 6th Gen Celica, a GT4 to upgrade my SR

I have swapped all the discs on my ST205 recently, took it for MOT and i noticed it is making a noise on some (possibly all) of the wheels, i think the sound is from the pads rubbing on the discs, the wheels spin without any considerable resistance.

I have been wondering if i did something wrong when fitting the discs. so here is my procedure.

take everything out.
push pistons back in the callipers
very light amount of copper grease is added on the "ears" of the pads, (so they can slide easier in the callipers)
also added a tiny amount of copper grease on the little U shaped bushings where they contact the calliper (on the other side, the pads have grease)
fitted the new discs (note i am using the old pads because they still have plenty to give)
retrofit everything.

Now this is the same procedure i have used when fitting discs on my parents Saab as well (with a small deviation as saab brakes dont have bushings, although they have some odd shaped springs) and their car is making more noise than mine.

The callipers on my car have been refurbished as part of the job and they have new square cut seals so i dont think there is any problem with the retracting of the pistons.

Im assuming im missing something very obvious, but from the youtube videos i checked there's nothing missing.

any ideas ?

[Bitter]

But DO NOT use the same 'copper grease' on any parts in contact with rubber!!! Use only silicone greases on those parts or brake slide pin specific grease.