Tools and Materials You'll Need:
* New coolant: Use the type recommended in your owner's manual (usually a 50/50 mix of coolant and distilled water). The amount needed depends on your truck's capacity; check your manual.
* Drain pan: Large enough to hold several gallons of coolant.
* Wrench: To remove the drain plug (likely a 13mm or 15mm).
* Funnel: To pour new coolant into the radiator.
* Hose: A garden hose is helpful for flushing.
* Protective gloves: To avoid skin contact with coolant.
* Safety glasses: To protect your eyes.
* Optional: Coolant flush kit (These can make the process easier but aren't strictly necessary).
Procedure:
1. Cool Down: Let the engine cool completely. Hot coolant can cause serious burns.
2. Locate Drain Plug: Find the radiator drain plug at the bottom of the radiator. The lower hose may also have a drain plug which might be easier to access.
3. Drain Coolant: Place the drain pan under the drain plug(s) and carefully remove the plug. Let the coolant drain completely. This may take some time.
4. Flush Radiator: Once drained, connect a garden hose to the radiator's fill neck (where you add coolant). Turn on the water slowly to avoid splashing, and let it flow through the radiator for a few minutes. This helps remove any remaining old coolant and debris.
5. Flush Engine Block (Optional but Recommended): Some vehicles have a block drain plug. If yours does, locate and open it to drain coolant from the engine block. Flush the block as well with the garden hose if possible. This is important to remove old coolant completely. Many F-150s do *not* have a readily accessible block drain, making this step more difficult.
6. Close Drain Plugs: Once flushing is complete, replace the drain plugs and tighten securely.
7. Fill Radiator: Using the funnel, carefully pour the pre-mixed coolant into the radiator until it's filled to the correct level (check your owner's manual).
8. Run Engine: Start the engine and let it run for 10-15 minutes, allowing the thermostat to open and circulate the coolant. Monitor the coolant level.
9. Check Coolant Level: Turn off the engine and let it cool down. Check the coolant level in the radiator and add more if necessary. Check for any leaks around the drain plugs or hoses.
10. Top Off: Over the next few days, monitor and top off the coolant level as necessary, as some air may work its way out of the system.
Important Considerations:
* Pressure Testing: For a more thorough flush, consider a pressure testing tool to force coolant through the system more effectively and to identify any leaks.
* Type of Coolant: Use the correct type of coolant for your vehicle (check your owner's manual). Mixing different types of coolant can be harmful.
* Professional Help: If you're not comfortable performing this task yourself, it's best to have a professional mechanic do it.
This procedure provides a general guideline. Always refer to your 1998 Ford F-150 owner's manual for the most accurate and detailed instructions. Improperly performed coolant flushes can lead to engine damage.
