From Moparts.com thoughts? Frequently we are asked if we can supply these plugs in brass. The answer is NO. Because the engine block is made of a ferrous metal (iron), everything in contact with the iron block and the coolant water should also be made of an iron-based metal. If you remember your high school chemistry class, you learned that if you immerse two dis-similar metals (iron and brass) in an electrolyte (the coolant water), you will have created a galvanic battery cell that will rapidly erode the least "noble" metal part (your engine bock). You don't want that! Making sure that any metal parts used in the cooling passages are made of a ferrous (iron-based) metal will keep the erosion to a minimum. There are mechanics that will try to install brass core plugs into yo
