Fitment: 2012-2013 Mazda 3 L4 2.0L excluding SkyActiv Models 2007-2011 Mazda 3 L4 2.0L 2007-2009 Mazda 3 excluding MAZDASPEED Models 2004-2006 Mazda 3 For more details,pls check compatibility Chart. What is an Expansion Tank on a car? The expansion tank absorbs excess coolant and minimizes excess pressure in the engine cooling system. An expansion tank helps maintain a minimal pressure increase during heated water expansion, helps reduce coolant hammer, and helps protect the engine cooling system from stress. Features: .
