How to flush the cooling system?

What's the beat way to flush the cooling system on a 2.7 I4?

 

have the coolant exchanged done by a machine...Should run you about $60-70.

 

drain and fill run for an hour drain and fill again. idk thats what i did worked pretty good.

 

I had mine done professionally. They did the service but I provided the fluid.

 

when i put in my sc, just drainging it wont even cut it, there is soo much that was held up, i would get it flushed

 

When my husband and I did it (years ago) and probably not the best way to do it, but it worked and nothing bad every happened after that.

Drain the radiator and fill it with water. Make sure the drain cock is closed. Start the truck and let it run until the thermostat opens up so the water cycles through the system. My husband actually had the radiator cap open and poured more water in as the thermostat opened since the system wasn't completely full. A couple minutes......shut the truck off, let it cool down. Drain the radiator again. I think we repeated that step twice (with water). Drain and put 50/50 anti-freeze in and once again, let the truck run and let the system cycle. This time - you need to watch the coolant level and top off as needed after the system cycles and works out the bubbles.

We used regular tap water for flushing. Used distilled water to mix with the anti-freeze.