How do you change the spark plugs on a 2004 Dodge Ram 1500?

Answer 1

It's not actually as bad as it looks, and is definitely a job you can tackle yourself, although each coil nut and plug takes a little bit different approach in my experience, and I needed a swivel, and a couple of different length extensions to do the job. If you have a good spark plug socket that will hold the spark plug, you can finger thread the plugs using it and a 6" extension.

To do the job to factory specs, you'll also need a torque wrench--a little 3/8" drive one that can handle 8-20 N-m and will fit in tight spaces is the way to go--some anti-seize compound for the spark plug threads, some silicone grease for the O-rings on the coils, and a source of compressed air. I really needed the compressed air. There was a bunch of dirt in the rear plug holes on both sides I wouldn't have wanted in my engine.

To get access to everything, remove the 10 mm bolt on either side of the resonator, release the four spring clips on the air filter box, release the the air filter box cover from the hooks on the engine side, then lift the front of the resonator to remove the plastic pin from the rubber grommet at the front of the resonator and work the resonator out of the rubber gasket that connects it to the throttle body. There is no clamp holding the resonator to the throttle body gasket, it just has a friction fit. Set the whole resonator/hose/air filter box top assembly aside. Stuff a clean shop rag in the throttle body gasket to keep dust from blowing into the throttle body. Remove the air filter and put it in a clean spot for the same reason. You may want to remove the left hand Allen screw on the resonator bracket and loosen the right hand screw so you can swivel the resonator bracket up out of the way to access the #1 coil nut with a socket.

Do one coil/plug at a time so there is no way you can drop a part in a cylinder!

Unplug the connector to the coil by pushing down on the release on the top of the plug and sliding them out of the coil.

After removing the 10 mm nut that holds each coil in place, use compressed air to blow out all the dust around the coil, then remove the coil (pull up gently with a little twisting motion back-and-forth) and blow all the dust around the spark plug out so you don't get anything nasty down in the cylinders.

Your OEM plugs are NGK ZFR6F-11G, gapped at 0.042-0.044 which you can get for about $2.44 each online.

Use the anti-seize compound on the spark plug threads so you can get them out next time. Finger-thread the plugs until they are snug, then torque them to 20 N-m.

A thin coat of the silicone grease goes on the O-ring on the coil to make it easier to install in the cylinder head and to make the O-ring last longer. Install the coil on the plug, then put the 10 mm nut back on to fasten the coil down. Torque the coil nut to 8 N-m. Re-connect the connector, and go on to the next plug.

If you have the right tools, this job is easier than doing it with an old distributor/plug wires setup, and the whole thing will cost you less than $20 including the plugs, the anti-seize and the silicone grease.