This replacement engine coolant thermostat housing assembly is engineered to match the fit and durability of the stock housing assembly on specified vehicles. It is designed to withstand extreme temperature changes to extend service life. Vehicle model years this part fits (be sure to check your vehicle trim using the Amazon garage) - [BMW 320i: 2001, 2002, 2003, 2004, 2005] - [BMW 323Ci: 2000] - [BMW 323i: 1999, 2000, 2001] - [BMW 323iC: 1998, 1999] - [BMW 325Ci: 2001, 2002, 2003, 2004, 2005, 2006] - [BMW 325i: 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006] - [BMW 325xi: 2001, 2002, 2003, 2004, 2005] - [BMW 328Ci: 2000] - [BMW 328i: 1999, 2000] - [BMW 328iC: 1999] - [BMW 330Ci: 2001, 2002, 2003, 2004, 2005, 2006] - [BMW 330i: 2001, 2002, 2003, 2004, 2005] - [BMW 330xi: 2001, 2002, 2003, 2004, 2005] - [BMW 525i: 2001, 2002, 2003, 2004, 2005] - [BMW 528i: 1999, 2000] - [BMW 528it: 1999, 2000] - [BMW 530i: 2001, 2002, 2003, 2004, 2005] - [BMW X3: 2004, 2005, 2006] - [BMW X5: 2001, 2002, 2003, 2004, 2005, 2006] - [BMW Z3: 1999, 2000, 2001, 2002] - [BMW Z4: 2003, 2004, 2005]