Recently purchased a low mileage (100 k miles) 2004 Durango with a 4.7L engine. It isn't giving me the mileage that it should. Went out today to install a set of iridium plugs. Pulled off the intake and found a clogged air filter. That explains part of the bad mileage. Getting at the coils isn't too difficult. But, dislodging the coils was a challenge. After removing disconnecting the wires and removing the nut that anchors the first coil pack, I could not pull it out. Tried one on the other side of the engine and same problem. Got out the PB Blaster and soaked the base of all 8 coil packs. Then went in the house to do some thinking on how to pry the danged things out.

Back outside, I tried using a long bar braced against a board. Nothing. Decided that mechanics must have a special tool to dislodge them. So after more thinking, pulled out my foot long needle nose pliers. I put the nut loosely back the bolt and put one side of the pliers on top of it and the other under the lip of the coil pack. Had to squeeze so hard I thought I'd break the coil. But it worked. Heard a loud pop as it broke loose. Same thing happened with the other 7 coils.

Pulled out the first spark plug. It was bad. There was just a nub of a post on it. Doubt the plugs were ever changed in a hundred thousand miles. Using the long pliers made the rest of the job go a whole lot quicker. I'm sure I'll see a lot better mileage and power after this tuneup.

Already did an oil change. Next I'll do a transmission service. Hope it's a more straight forward job than the spark plug installation. I've ordered a new transmission pan with a drain plug. I hate getting a face full of used transmission fluid whenever I change it because the stock pans don't have drain plugs. That's an intentional flaw by Dodge.

 

You may get to change the plugs again...... Unless the engine originally came with the rare earth plugs, they don't always care for them, and you end up with mystery misfires......

 

Well, now that I know the tricks, it will be a lot easier the next time. Didn't know that Durangos don't like the finer things in life. Guess the previous owner wanted to prove that the cheaper plugs can last over 100,000 miles.