B3000 SE Regular Cab 4WD V6-3.0L OHV (1998)
4. Flush the engine and radiator.
5. Install the water thermostat; refer to Thermostat Removal/Installation.
6. Back flush the heater core if necessary.
7. Fill the cooling system; refer to Engine Coolant Replacement.
Heater Core
1. Partially drain the cooling system; refer to Engine Coolant Replacement.
WARNING: Do not open the cooling system while it is hot or while the engine is running.
2. Back flush the heater core.
3. Fill the cooling system; refer to Engine Coolant Replacement.