Here's how to do it:
1. Locate the drain petcock: The radiator drain petcock is typically located at the bottom of the radiator, usually on the driver's side. It's a small valve.
2. Position a drain pan: Place a large drain pan (at least 5 gallons capacity) underneath the radiator drain petcock to catch the coolant. The capacity of your Tahoe's cooling system is around 12 quarts.
3. Open the drain petcock: Carefully open the drain petcock by turning it counter-clockwise. The coolant will start flowing out. Be careful, as it might initially flow quickly.
4. Open the radiator cap (optional but recommended): After the initial flow slows, open the radiator cap to allow for more complete draining. This will release any pressure and allow more coolant to drain out. Remember to do this only after the pressure has released from the initial draining!
5. Wait for complete draining: Allow sufficient time for all the coolant to drain from the radiator. This can take 15-20 minutes.
6. Close the drain petcock: Once the flow stops, carefully close the drain petcock by turning it clockwise. Make sure it's securely closed to prevent leaks.
7. Remove the drain pan: Carefully remove the drain pan once you're sure all the coolant has drained.
8. Dispose of coolant properly: Coolant is toxic and must be disposed of properly. Check with your local waste management facility or auto parts store for proper disposal methods.
Important Considerations:
* Overflow Bottle: You might want to remove the coolant from the overflow bottle as well. This can often be done by squeezing the bottle to get most of the coolant out.
* Engine Block Drain: For a more thorough drain, you may also want to drain the coolant from the engine block. This typically involves locating a drain plug on the engine block itself (location varies by engine type; consult your owner's manual). This step is more involved and may require additional tools.
* Owner's Manual: Always consult your 1999 Chevy Tahoe's owner's manual for the precise location of the drain petcock and any specific instructions for your vehicle. Your manual will also show you the recommended type and amount of coolant to refill with.
Remember safety first. Wear gloves to protect your hands from the coolant. If you're unsure about any part of this process, it's always best to consult a qualified mechanic.
