pajarony i m guessing you re talking about the red paint scratched surfaces. i get that effect by using a trishader. the first shader is a dark matalic material with high difference between bright and dark areas. the second shader is a very shiny metal, like a chrome surface.
( both are matcaps i ve created myself by manipulating photos. the first was a photo of an old sterling silver statue. the second was from a picture of a small chrome ball, the one you find in a whiskey bottle to control the flow)
the third shader, i created following this tutorial, this guy has done a really good job. i just combine them all together and by changing the values of cavity ambient and dffuse i get different results.
hope this helps.