I have noted increased enthusiasm for changing oil drain crush washers at every oil change. I have never landed on a solid opinion here and wonder what is true. Are crush washers deformed, and forever changed after one crush? Is there any actual design that goes into crush washers? Is there a difference between the golden ones and the silver ones? If they are not to be reused, can we account for people who never change them and never have failures? On the same note, has anyone ever heard of a crush washer failure?