Thinking about purchasing a new car? Use our new Car Loan Calculator to estimate your monthly car payment!

How to Drain the Radiator on a Sierra

by Tara Kimball

Monitor the condition and level of coolant in your GMC Sierra regularly. When the coolant begins to degrade, change color or show debris, drain the radiator completely before replacing the coolant. The Sierra provides an easily accessible radiator drain at the base of the radiator. When refilling your engine coolant, use a 50/50 mixture of pure, clean water and anti-freeze for optimal performance.

Raise the Sierra with a jack and position it on a set of jack stands. Allow the engine to cool completely if the truck has been running.

Position a large drain pan or bucket beneath the radiator drain plug. The drain plug on the GMC Sierra is located at the base of the radiator on the driver side of the truck.

Loosen the radiator drain plug with a wrench. Turn the plug counterclockwise to loosen it until coolant flows from the drain.

Allow the coolant to drain completely from the radiator. Replace and tighten the radiator drain plug using a wrench.

Items you will need


About the Author

Tara Kimball is a former accounting professional with more than 10 years of experience in corporate finance and small business accounting. She has also worked in desktop support and network management. Her articles have appeared in various online publications.

More Articles

Photo Credits

  • radiator humor image by John Sfondilias from