The 50k maintenance schedule is due on the Enclave, if you follow these posts; you will know that since the previous post was the transmission fluid change, the next step would be to flush and fill the coolant; the following post is how to accomplish that.
I did this with the car flat on the ground so there is no
need to jack it up.
You will need to remove the giant plastic shroud to gain access to the radiator cap which is under the upraised section of the shroud.
There are a bunch of plastic clips that need to be popped out to remove it. I used a flat head screwdriver to lift up the clip and then used the channel locks to take them out.
There are also a few rubber screws in pieces that need to be removed. You can just unscrew them by hand, they came out pretty easy.
Now you can take off the plastic shroud to reveal the top of the radiator. Be careful towards the top, there is some rubber weather stripping that will need to come off of the shroud to completely remove it and it is held in with small push in plastic clips. Just pull them gently straight up, you may need to wiggle it a little bit….
Remove the radiator cap from the top of the radiator.
Position your catch can for the coolant underneath the lower radiator hose.
Use the Channel Locks to squeeze the ends of the clip together and loosen the clamp.
Slide the lower radiator hose off of the radiator. Be prepared to get coolant all over the place, this is a messy job but it’s just coolant.
Let all of the coolant drain from the radiator.
Replace the lower radiator hose, I left the catch on the
clip on so the clamp was loose, knowing that I was going to remove it again.
Turn the car on and let it warm up until the temperature is
at its normal operating position. You want
the thermostat to open and the coolant that was behind it to circulate through.
Once you are convinced that the thermostat has opened and
coolant is circulating through the block, turn the car off. You can tell when this has happened because the
water will change color to the color of the coolant.
Drain the radiator again.
Once the radiator is fully drained, reconnect the lower
radiator hose and release the hold on the clamp so that the clamp is once again
tight around the hose.
Mix the coolant so that it is 50% coolant and 50% distilled water. I will normally use one of the distilled jugs that I emptied into the radiator previously and fill it half way with coolant, then top it off with distilled water. I will then fill the coolant jug to the top with distilled water as well. You will now have 2 gallons of 50/50 mix coolant.
Fill the radiator with the coolant mix. Start the car and let it get to operating temperature. Keep an eye on the level of the coolant, when the thermostat opens it will take the coolant level down and you will need to put more in. There will also be air bubbles that come out while the coolant starts to circulate. Keep filling the radiator until there are no more bubbles.
Replace the radiator cap and make sure the overflow is at
the right level.
Replace the plastic shroud that you had to remove and you