How to Replace Spark Plugs in a Chevy Avalancheby ContributorUpdated November 07, 2017
Items you will need
Spark plug wire pullers
Socket wrench with extender
New spark plugs
How to Replace Spark Plugs in a Chevy Avalanche. All Chevy Avalanche year models are equipped with platinum-tipped spark plugs. These spark plugs are designed to work for up to 100,000 miles before replacement is needed. If an Avalanche model's engine becomes sluggish, uses more gas or misfires, check the spark plugs for damage or dirt.
Pop the hood and allow the engine to cool. Do not remove a spark plug from a warm engine.
Locate the spark plug wires. Some Avalanche models have spark plugs running along the sides of the engine, below the engine cover. Other models have spark plugs on top of the engine.
Remove one wire from a spark plug. Clamp the wire puller on the boot, or tip, of the spark plug wire, turn it 180-degrees to the left and pull out. If you remove more than one wire at a time, they need to be marked. If a wire is connected to the wrong spark plug, the engine will misfire.
Attach the socket to the spark plug and turn it counter-clockwise to loosen the spark plug. Remove the socket and turn the plug by hand to release it from the cylinder block. Do not use a flexible extender on spark plugs.
Brush out the wire boot and the spark plug in the engine. Be careful because scrubbing too hard causes damage to the thread and boot.
Spread a thin coat of anti-seize compound over the thread of the new spark plug and insert it into the well. Turn the spark plug to the right to tighten it.
Tighten the spark plug 1/4 turn with the socket to set the plug.
Replace the spark plug wire and turn it 180-degrees to the right and to the left until you feel or hear a click. Repeat Steps 2 through 7 for each spark plug.