Proper radiator maintenance requires that you periodically flush the cooling system in your car, truck, or SUV. By properly maintaining your cooling system, your car radiator will last longer, perform better, and remain reliable. A poorly maintained radiator cooling system can accumulate rust, corrosion, and sediment in the system, which will degrade your car, truck, or SUV radiator’s cooling capacity and can ultimately lead to engine damage or a breakdown.

Flushing your cooling system is a relatively simple procedure that will keep your cooling system running better, for longer.

Tools you need: a catch basin, a screwdriver, and a crescent wrench.

First you must drain your cooling system. The only major difference between car radiators, truck radiators, and SUV radiators are the relative sizes of the cooling systems.

To drain the coolant from your cooling system, do the following:

Remove the radiator cap
Place the catch basin below the radiator drain
Remove the radiator drain plug (Warning: if the vehicle has been running, wait for it to cool before doing this)
Let the radiator drain
Move the catch basin underneath the engine block
Remove the engine block drain plugs
Let the coolant drain from the engine block

Now that the coolant system is empty, check all the radiator hoses, fastenings, and connections. If any part is badly corroded, broken, or leaky, replace or repair it.

Now you must flush the cooling system:

The easiest way to flush the system is with a garden hose, but several buckets of clean water will do just as well.
Run water through the radiator until it runs clear
Remove the hose from the overflow tank and flush both it and the overflow tank
Reconnect the hoses and replace the drain plugs

Once the drain plugs and hoses are back in place, you can refill your cooling system:

Add the fresh coolant to the system (a 50/50 mix of anti-freeze and water), filling up the radiator and reservoir
Leaving the cap off the radiator, start your car, truck, or SUV
Wait for the thermostat to open (coolant will start flowing through the system and the level will drop in the reservoir as the engine refills)
Turn off the engine
Top up the coolant in the reservoir
Replace the radiator cap

And that’s it. Your car, truck, or SUV’s radiator cooling system has now been flushed!