Fix-It Fred: Spark Plugs

Last week at work, I had a momentary revival of my man card. I was having a conversation with some of the guys about vehicles and oil changes. Sometime during the conversation, I opened the electronic version of my owner’s manual to verify the oil quantity. As I scrolled through the pages of maintenance schedules, I noticed something I did not remember seeing before: my vehicle was due for a spark plug change at 30,000 miles.

What sort of archaic car do I drive that requires a change so soon? A 2013 Dodge Durango. It is definitely new enough to expect the typical 100,000-mile spark plug change seen on most newer vehicles. It turns out that Dodge/Ram/Jeep decided that their Hemi engines required a plug change reminiscent of when they were first put into production in the early 1950s.

It appears that anything with the 5.7L engine model year 2013 and older (at least to 2010, but I am not sure how far back) has this same spark plug change interval. There was a change made so the 2014 model year and newer cars only need the work done every 100,000 miles.

Even though the spark plug information was a surprise, the timing of the finding was pretty good. We have barely over 30,000 miles on our car and I was planning to spend some time doing routine maintenance anyway. So, after purchasing the supplies, it was time to tackle the project. The filters were easy and straightforward. The plugs took a little more time and were not so simple. Below I will go through the process I found easiest.

2013 hemi plug change supplies

One thing to note, this engine has two spark plugs per cylinder, for a total of 16 plugs to complete the change.

The first step is to gather the required tools for the job. Here is a list of the tools I used:
1/4” drive ratchet
3” extension for 1/4” ratchet
10mm socket for 1/4” ratchet
3/8” drive ratchet
3” extension for 3/8” ratchet
6” extension for 3/8” ratchet
5/8” socket for 3/8” ratchet
Spark plug gap tool/gauge

2103 durango hemi spark plug tools

The project would have been slightly easier with two 3” extensions or a swivel joint for the 3/8” ratchet. Cylinders 2 and 6 were a challenge due to the shock tower and fuse box locations. They would have been easier with the additional extension or the swivel, but with the tools I had on hand they were a bit tricky. There is a map of the cylinders included in one of the pictures below if you are curious which cylinders are numbers 2 and 6.

durango rt spark plug change

Once I had all the tools I needed it was time to dig under the hood. To begin with, I removed the engine cover. To do this, I simply grabbed the front edge and pulled up. Four rubber ball and socket posts keep it in place on the engine (blue circles below). Once it is loose, it then lifts off easily. After this was out of the way, I could see what I was working with.

engine layout

The engine compartment in this vehicle is laid out relatively well. There was enough room to at least access all the cylinders. While a couple were difficult given my tool selection, the rest were workable. Some of the other cylinders had some hoses and tubes in the way, but nothing major. A little creativity with the use of both extensions for the 3/8″ ratchet led to a relatively successful spark plug swap.

durango hemi spark plug coil pack

The first step in the process was to remove the coil pack from each cylinder. I removed a couple at a time as I changed the plugs so I could keep the coils straight and not risk dropping anything in around the spark plugs. Each coil is held on with 2 M10 screws. The screws can be seen in the picture above. Some screws required the use of the extension on the 1/4″ ratchet, others did not.

2013 hemi 2 plug coil pack

Looking at the picture below, with the coil packs removed, you can see how far down into the head the spark plugs are. Hence why a 6″ extension is required. The picture above shows the boots for two plugs on each coil. With the spark plugs accessible, the rest of the job was simple. Remove the old plugs. Verify the gap on the new ones, and install them. Once all the plugs were installed, I verified the coils were all seated and tightened down.

durango hemi 2 spark plugs

After the new plugs and filters were installed it was time to check my work. With the push of a button the engine came to life, and idled smoothly. Step one was a success. The next step was to take it for a quick test drive to make sure it ran smoothly. The plugs did their job. The engine ran great, without any hesitation or lag. I had not noticed that the engine had lost a little until after the new plugs were in.

Another successful afternoon in the garage.

Do you have any vehicle maintenance tips and tricks? Share them in a comment or email.