Wehrli 01-05 Duramax LB7/LLY Thermostat Housing Kit - Candy TealThe Top Outlet Billet Thermostat Housing and Upper Coolant Pipe Kit for 2001 2005 LB7 LLY 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 turbochargers, and updates engine bay