Cooling systems are tricky to work with. Everything will be functioning properly, and then all of a sudden, something as simple as an air bubble can cause your vehicle to overheat. So how do you get out air bubbles? Just like a baby, you burp the cooling system--and it's easy to do.
Pop the hood on the truck and prop it up using the hood prop. Make sure the vehicle has been sitting and is cold before starting this process.
Locate the radiator filler cap on the radiator and open it. It will take two turns, one counter-clockwise and then another counter-clockwise while pushing down on the cap.
Add coolant to the radiator, using the funnel. You want a 50/50 ratio of distilled water to coolant, but Prestone also sells a premixed coolant that works well. (See References for info.)
Run the vehicle with the radiator cap off. Watch the coolant level in the radiator. It will bubble and pop a bit and you'll know that it's been burped when the coolant level drops a large amount.
Fill up the radiator to the top with the 50/50 mix. Make sure not to pour it in too quickly, because you don't want to put more bubbles into the system. Put the radiator cap back on the radiator and tighten it down.
Let the cooling system run again, while watching the temperature gauge in your truck. If it still runs hot, there may still be an air bubble in the system, so start the process again.
