Removing the Thermostat

• 1). Place a drain pan underneath the radiator. Loosen the petcock valve with a crescent wrench. Allow the coolant to flow in to the drain pan. Close the petcock valve when the coolant is through draining.
  
  
• 2). Remove the splash guard with a socket wrench. This will give you more room to access the thermostat housing.
  
  
• 3). Pull the bottom radiator hose off the thermostat housing with a pair of pliers. Squeeze the tabs at the top of the hose clamp to loosen the clamp and pull the hose off the thermostat housing.
  
  
• 4). Unbolt the thermostat housing with a socket wrench. Pull the housing cover away from the housing.
  
  
• 5). Pull the thermostat out of the housing with your fingers. The thermostat will come out with no resistance.
  
  

Installing the Thermostat

• 1). Place the new thermostat in the housing. Ensure it is positioned the same as the previous one.
  
  
• 2). Bolt the thermostat housing cover to the housing with a socket wrench. Ensure the bolts are snug.
  
  
• 3). Push the radiator hose to the thermostat housing. TIghten the clamp over the hose and the pipe.
  
  
• 4). Tighten the splash guard to the bottom of the truck with a socket wrench. Ensure all the bolts are tight and the guard is secure.
  
  
• 5). Open the hood to access the engine compartment. Unscrew the radiator cap with your hands.
  
  
• 6). Fill the radiator with coolant. Start the vehicle and allow it to idle. Once the engine is warm, this will open the thermostat and require more coolant to fill the system. Top off the radiator with coolant. Fill until the coolant is visible at the neck of the radiator. Screw the pressure cap back on to the radiator.