GM 22729533
Heater Core

The engine coolant must be drained before initiating the heater core replacement. The first process involves unclipping and removing the heater outlet hose from the heater core before proceeding to unclip and remove the heater inlet hose from the core. The replacement process begins when you eliminate the instrument panel retainer while also removing the shift control together with heater duct screws and the heater duct. You must unscrew the heater core cover screws to access the cover and the heater core pipe cover screws for that purpose as well. Also disassemble the heater core pipe foam seal. You should grasp the heater core by its end tanks before taking it out while mixing soap and water to spray the heater core seal and pipes located at the dash front for easier extraction. Place the new heater core in position while spraying the perimeter of its front dash pipes along with their heater core seal using a soap water mix for easier placement. The heater core pipe seal should be installed along with the heater core pipe cover which requires tightening to 1 N.m (9 lb in). Spray the opening on the dash seal with front-facing drain tube to aid cover installation. Then add the cover and fasten it using screws which should be tightened to 1 N.m (9 lb in). Replace the heater duct first and then its screws should be tightened to 1 N.m (9 lb in). Next install the instrument panel retainer and shift control bracket. The last step involves connecting the heater inlet hose followed by applying the clamp before proceeding with the heater outlet hose and its clamp. Before continuing the procedure, the cooling system requires a fill.