Safety First:
* Let the engine cool completely before starting. A hot engine and coolant can cause serious burns.
* Wear safety glasses to protect your eyes from splashes.
* Work in a well-ventilated area. Coolant is toxic.
* Have the proper tools and supplies ready before you begin.
Tools and Supplies You'll Need:
* Drain pan: Large enough to hold several gallons of coolant.
* Wrench: Appropriate size for your radiator drain petcock (usually located at the bottom of the radiator).
* Hose: A garden hose is sufficient for flushing.
* Funnel: To help pour coolant back into the radiator.
* New coolant: Use the type recommended in your owner's manual (usually a 50/50 mix of coolant and distilled water).
* Gloves: To protect your hands from the coolant.
* Clean rags or shop towels.
Steps to Flush the Radiator:
1. Locate the Radiator Drain Petcock: This is usually a valve at the bottom of the radiator.
2. Position the Drain Pan: Place the drain pan under the radiator drain petcock.
3. Open the Drain Petcock: Carefully open the petcock to drain the coolant. Let it drain completely.
4. Open the Radiator Cap: Once the coolant has stopped draining, carefully open the radiator cap (after the engine has completely cooled!). This allows for more complete draining.
5. Flush with Water: Connect your garden hose to the radiator's top hose opening (where the upper radiator hose connects). Turn on the water slowly, allowing it to flow through the radiator and out the drain petcock. Continue flushing until the water runs clear.
6. Close the Drain Petcock: Once the water runs clear, close the radiator drain petcock tightly.
7. Reconnect the Radiator Cap: Carefully replace the radiator cap.
8. Refill with Coolant: Using a funnel, add the correct amount of new coolant mixture (refer to your owner's manual for the correct amount and type). Do not overfill.
9. Bleed the Air: Start the engine and let it run for a few minutes to allow the coolant to circulate and bleed out any trapped air. Check the coolant level and add more if needed. The upper hose should get warm, indicating circulation.
10. Check for Leaks: Inspect the system for any leaks.
11. Top Off Coolant: Once the engine has cooled, check the coolant level again and top it off to the proper level.
Important Considerations:
* Power Flush: For a more thorough cleaning, consider using a radiator flush kit from an auto parts store. Follow the kit's instructions carefully.
* Coolant Type: Use the correct type of coolant specified in your owner's manual. Mixing different types can damage your engine.
* Disposal: Properly dispose of the old coolant according to your local regulations. It's toxic and should not be poured down the drain or onto the ground.
This guide provides general instructions. Always refer to your Silverado's owner's manual for specific details and safety precautions relevant to your model year and engine. If you are not comfortable performing this task yourself, it's best to take your vehicle to a qualified mechanic.
