WCFAB 2006-2010 LBZ/LMM Duramax Top Outlet Billet Thermostat Housing & Upper Coolant Pipe KitPowdercoat colors can be found here! The Top Outlet Billet Thermostat Housing and Upper Coolant Pipe Kit for 2006 2010 LBZ LMM Duramax replaces the OEM upper radiator hose that normally crosses over the driver side valve cover as well as the coolant return pipe. By changing the coolant routing to an upwards and forward layout from the thermostat, this kit improves access to driver side fuel system components, adds room for larger aftermarket