3.4. 3.8 LITER. Drain plug. W/O GT3. A removable Plug that allows the coolant pipe to be Drained. A removable Plug which allows the Engine Coolant Inlet Housing to be Drained. Plug that prevents the Engine block or cylinder head from cracking in case of freezing coolant. Also used to Plug the casting holes from production. Removable Plug located in the Thermostat Housing that allows to Drain the Engine Coolant. Coolant Inlet Flange. Coolant Pipe. Coolant Thermostat Housing. Core. Expansion. Freeze. Welch. Thermostat hsng. Transmission Screw. Water Inlet tube. Included with: Tube, Water pipe.