Spark plugs are among the cheapest engine parts, although they are important in making sure your engine runs properly. A spark plug delivers a charge to cause the fuel and air mixture in the engine’s cylinders to combust, thereby cranking the cylinders and turning your engine. Spark plugs wear out over time, though, and sometimes they altogether fail due to uneven wear or corrosion. You will, therefore, need to replace your spark plugs at regular intervals.
Spark plug replacement is usually part of any automobile’s regular preventive maintenance service, although you can do this yourself. On a Chevy Silverado, the manual recommends a spark plug change every 60,000 to 100,000 miles, depending on your driving habits and the condition of your truck. Various Chevy Silverado models have different spark plug usage life cycles, but the process of replacement is common.
Tools and preparation. Before working on your engine, make sure to let it cool a couple of hours after use, so that you will not be injured by the engine’s heat. You will need a socket wrench with extension so you can reach the spark plugs from within the engine block. You will also need a 5/8 spark plug socket, silicone lubricant, a wire brush, tensioner tester and a new set of spark plugs. Depending on your truck’s engine configuration, you will need six or eight spark plugs for V6 and V8 engines, respectively.
Gain access to the spark plugs. Pop up and prop up the hood. You will need to disconnect your car’s electrical system to reduce the risk of electric shock. Disconnect the battery from the negative terminal. Then, open the engine block cover (if present) by lifting it to the side.
Loosen the spark plug wires and then remove them. You will need to grasp each spark plug wire by the boot, twist it to the left and right until you can pull it out. Take note of the placement of wires, as these are attached in order.
Remove the spark plugs. Insert the socket wrench into the spark plug bay, and make sure the end fits snugly. Unscrew the spark plug by turning counterclockwise until the spark plug goes loose. Pull out the spark plug and then set aside.
Prepare the new spark plugs. Use your wire brush to clean the inside of the wire boot. Then, apply silicon lubricant to both the contact of the new spark plug and the interior of the wire boot. Insert the new spark plug into the socket, and twist clockwise with your hand. Use a tension tester tool to check for correct torque. The correct tension is usually indicated in the spark plug’s container or packaging. Use your socket wrench to adjust the tightness accordingly, turning clockwise to tighten and counterclockwise to loosen.
Reinstall the spark plug wires, taking note of the order. Make sure the wire boot clicks into place, indicating a snug fit. Then, replace the engine block cover, and reinstall the negative battery wire to the terminal. Most newer car engines will not need a tune-up, so you’re good to go.