The procedures for replacing/changing spark plugs on the Ford Expedition, Lincoln Navigator, & F-150 Triton.

I just replaced my spark plugs on my 1998 Ford Expedition. It was much harder than I'm used to (I have a 1989 Jeep Cherokee with the inline six, and I can change the plugs on that in about 10 minutes).
Anyways, I've outlined the procedures that I used. Don't rely on a store-bought repair manual as the instructions are way too vague.

Here are the instructions verbatim. If you want the instructions with photo examples just follow the link at the bottom.

Hope this helps,

V


I just finished up replacing the spark plugs on my 1998 Ford Expedition with the 5.4 Triton V8. (This was a pain in the @ss; I owned a 1990 Ford Thunderbird and I thought those were horrible). Anyways, after searching the internet I found some very good tips on several site forums. I used these tips along with some additional steps that I thought would definitely help make the task less stressful. The additional steps may seem extensive, but they help make the task much easier, and like I said, LESS STRESSFUL!
First off, don't bother relying on a store-bought repair manual like the one I own. The instructions are so vague, they pretty much just tell you to remove the coil packs and remove/replace the plugs.
The best method involves using a foam pad (or thick padded carpet) and setting it over the radiator and top of the engine. You'll need a stool or chair to secure your footing while lying across the engine bay on this.
You will need a good assortment of extentions and swivels in 1/4" & 3/8" drive if possible.
If done correctly, it should take between 1-2 hours.
First as usual, disconnect the neg. on the battery.

Lay the padding across the radiator/engine bay.

When doing this job you'll end up looking kinda like this.....(I recommend using something much more stable than this little stool I used).

Remove the plastic cover covering the throttle body. (Three 10mm bolts)

Remove power connection terminal cover on the passenger side near the battery (this pops off when you pull downward & out at the bottom of it)

Remove three 13mm nuts and the cables. (make sure you mark them so you put them back where they were). Next, remove the two 8mm bolts holding the entire assembly to the firewall. Pull away from the firewall. Now you will be able to have easier access to the #1? spark plug farthest back on passenger side. I feel that this is the hardest one to change.


Remove the three 8mm bolts & remove the plate that secures the power steering reservoir in order to access the #5 spark plug.

Replace each spark plug one at a time. On the driver side you may need to remove the two 8mm bolts securing the fuel rail. You may need to pull the fuel rail up and away slightly to clear the check valve and access the #6 spark plug. Make sure you blow away all debris before removing the fuel rail. You do not want anything falling into the manifold. This would be HORRIBLE! Also, only pull the fuel rail away as far as neccisary to access/remove the bolt securing the coil pack and the coil pack itself. Debris (or a dropped coil pack bolt)could possibly fall into the manifold through the injector ports! Again, this would be HORRIBLE!

Attach a small section of hose to reach the hard-to-reach areas. You need to blow out the spark plug holes BEFORE you remove the plugs to prevent debris from falling into the cylinders. And yes, this would be HORRIBLE!

Also, make sure you coat the spark plug threads with anti-seize, and coat the inside of the boots with dielectric grease. This will prevent corrosion, heat damage, and prevent the boots from sticking on the next replacement. Gap the plug to specs before installation.

After taking your time and being patient, you will find yourself finishing up this job and feeling a great sense of accomplishment. Bolt all parts back up to where they were, and re-check all of your connections to include connections to the coil packs, injectors, and also inspect surrounding vacuum hoses to see if they were accidently disconnected when moving them around to access the spark plugs (the PCV valve kept popping out when I did mine).

Hinesight is always 20/20, but I'm pretty sure I could do this again in under 1 hour. Remember, take your time, be patient, be careful, and take a breather if you need it!

Enjoy,
Vic

here's the link to my web page with accompanying photos:
http://www.angelfire.com/sd/vmkrampi...ug_change.html

 

Great instructions. One comment: I would add torque spec for tightening the sparkplugs as many of us know how important that is with the 5.4 engines.

 

Thanks 98expedition XLT,
Very important to tighten these plugs to manf. spec. In addition to the history of these engines blowing out plugs, overtightening spark plugs on these could easily result in stripped or damaged threads. That would only increase the chances of a "blown-out" plug.

Thanks again,
V

 

I[FONT=Arial] just replaced the plugs on my 99 Expedition, 142K now. Your method and information was very valuable. I was apprenhesive about tackeling this project after reading others HORROR stories. The #4 and #8 plugs were a real CHALLENGE but the impediments were overcome. I purchased a 5 -80 ft/lb 3/8 drive torque wrench and torqued the plugs to 17 ft/lbs. I guess I saved about $500.00 over what a dealer would have charged for the same job. I took my time and have only one owie on my left thumb.
Thanks for your wonderful information.

 

Oh I almost forgot a TIP. If you are vertically challenged like me (5'7) you can lower the front by jacking up the rear as high as you can. Then you don;t have to climb and reach as far. This worked real good for me. If you took the front wheels off you could lower the front even more.

 

Really great instructions and pics on website. I'm still apprehensive about tackling this project but I'm willing to give it a try. I also want to do a tune-up on a '01 EXPLORER SPORT-TRAC. Any suggestions?

 

I tourqe the plugs in 2 stages, 1st - 120 in.lb, reset to 168 in/lb and tighten till it clicks, repeat 7 times. You can pick up a decent in/lb tourqe wrench at parts america for $28

 

Great post, however in your list of tools you forgot the cold pack of beer

 

Great tips on changing the plugs, I will be doing this in the spring.
~Gage~

 

The book (and Ford) call for 9-20 Nm (7-15 lb ft) on the plugs: 17 lb ft is too tight, you could risk stressing the threads by adding that extra 2 lb-ft, go to 11-13 lb ft or as close to that as you can get puts you in the zone, so when I did it, I hit 13 lb-ft to be safe, and this was because I called the factory and the 5.4 designers (who are doing the lifecycle maintenance profile on that engine) and made sure they meant 7-15, and they did, so I opted for the 13 because the engine materials guy said 13 is perfect (allowing for expansion from heat, etc.). Just my experience/$.02. (BTW; I went back and rechecked the torque on all of mine last week after about a month of driving and about 1k miles. All of them are exactly at 13.)

https://www.ford-trucks.com/forums/6...ml#post5503278

 

I just received a quote from the Ford dealer to replace the plugs in my 2004, F150 5.4. The quote was $394.00 plus 2 hours for each plug that breaks during removal. Total around $2,000.00 to replace 8 spark plugs.

I chose to take it to a reliable mechanic that does other work for me and his quote was about 100 dollars cheaper than the 394. The first 2 plugs that he removed the bottom broke in the head. To remove the broken end is very difficult and the back 2 cylinders are not possible with the tools available from Snap-On. He stopped and called me and I told him not to proceed. He said the only way he could remove the back 2 if they did not come out in 1 piece is to remove the heads @ 20 hours.

How can Ford with the best selling truck in America design a vehicle that costs over $2,000.00 dollar to replace the spark plugs?

Now you understand my name, Jim Xfordowner. I'm going to trade this great truck, untill now, for a Toyota.

 

WOW, 2000 bucks seems a bit pricey. I just replaced both set of cats, eight plugs and all the cops for about 1300. I purchased the COPS online and I also bought the cats online and had them delivered to my mech. Dumb, me, though, I let him charge me 10 bucks a plug. I forgot to pick those up.

500 bucks for the catalytic converter
80 bucks for the plugs.
About 650 bucks in labor.
20 bucks for a fuel filter.
2 bucks for an exhaust clamp.

Also had the DPFE hose changed out. I guess it was starting to melt....

By the way, all this started because I had a misfire and didnt get to it in time. Clogged up my cats, only 2psi out of the right side.

Now, she purrs like a mean motor city Kitty.

I love this truck!!!

2000 Expedition Eddie Bauer
4WD
V8 5.4l

 

How many miles are on your truck? Is this the first time changing your plugs? Why are these mechanics almost guaranteeing you that the plugs will break off in the head? Sounds like a set up to me.

 

How many miles on your truck? Were those the original cats?

 

125 K miles. And yeah, they were the originals. I bought the replacement cats from racepages.com They will give you a 10% discount if you ask for it.