An easy way to flush a radiator is to remove the bottom hose from the radiator, and put a garden hose in the top fill hole, turn the water on, on the garden hose and let the water push the water out of the radiator. Do not start the truck. This is for flushing a radiator, not an engine. Dont forget to reattatch the bottom hose and refill the radiator as water will also flow out of the engine and will now be low.
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