New brake pads
When you have mounted new brake pads, they have to be run in:
Do 5 - 8 stops from 80kmh to 20kmh. The first ones a bit careful, and then more and more brutal. NB! There must be no cars behind you!
Don't stop completely, and keep driving for a while after you are finished, so your brakes get a chance to cool down.
Important: If you have braked hard and stopped completely, you must not continue to hold the brake pedal down; it might damage the brake disc. Apply the hand brakes in stead.
It would also be good if the wheels can move a little bit, so the hot brake pads don't keep in contact with the brake discs in the same place.