You guys are doing this the hard way. I work on many cooling systems at work and I flush all of them. Pull both rad hoses off at the engine. Use a garden hose with a sprayer and run water through one rad hose and out the other. Cycle back and forth between the hoses until clean water homes out.

Now, pull the t-stat. Stick the sprayer in the t-stat hole. Run water through until clean water comes out the other side of the engine.

Put t-stat back in and hoses back on. Refill system. Make to to be strong on the antifreeze mix because there will be a lot of water in the engine and lower rad.

 

I removed the air dam because, the engineer's in their infinite wisdom, covered the drain **** with it The drain plug on my Monte Carlo is impossible to get to or find without pulling that plastic air dam!

No big deal, just 5 screws to remove. Then the challenging part was locating the drain **** It is kind of hidden just above the metal radiator housing on the drivers side.

Anyway, I am done with that bit of maintenance and thankful that I found this forum.

PS: I am now the proud owner of a Haynes Repair Manual.

 

You don't have to remove the air dam. Reach above the crossmember with a 19mm deep socket until you find the drain. It will drain through the air dam.

 

So no one is suggesting a backflush except one person and it was on the radiator. Is it just not necessary?
Bringing this thread alive again!!