These washers are good quality and do a good job. I have read all of these comments and the negative comments are related to oil leaks. If you do a thorough research you will find that Mazda engines, especially Skyactiv, have a tendency to lose oil through the drain plug, which means that plug needs to be replaced as well. If you have an M18 hex drain plug, they will leak after your engine has run 80,000 to 90,000 miles. This is not the fault of the crush washers, also replace the drain plug…