PrairieDrifter
Full Access Member
- Joined
- Dec 28, 2014
- Posts
- 3,877
- Reaction score
- 5,710
- Location
- North Dakota
- First Name
- Mason
- Truck Year
- 84,79,77,76,70,48
- Truck Model
- Suburban k10, bonanza k10, k30, k20, c10, gmc 1/2ton
- Engine Size
- 350, 350, 350, 350, 350, 350
Fill your cooling system up, start the truck up, top off the cooling system while it’s running then cap it off and let it idle up to running temp for a about five minutes. Then shut it down wait a couple minutes and then be REALLY careful and pop off the bottom radiator hose off the radiator. Do this from the top as well so you don’t get soaked in hot coolant.
Do this until the water starts coming out clean, might take 2 or 3 try’s depending on how bad your system is. Use your best judgement on which flush will be your last, with the last flush you’ll want to flush it with distilled water just to get out any non distilled water. I just use big water jugs from Walmart or something.
Then depending where you live, you’ll want at least a 50/50 mix of distilled water and antifreeze. I live up North so I run a little bit heavier on the antifreeze.
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