Hi all, New to the forum. I've been reading through all the threads about replacing spark plugs on the 2004-2008 F150s. Grateful for all your posts. I'm looking at purchasing an early 2008 (pre-changeover) 5.4L XLT with 122k miles on it and original plugs. From the posts, it seems like replacing the plugs is doable with a lot of patience, care, the right tools, and hours or days to spare. Anyone have any horror stories that I should be aware of? The truck seems to be in good shape otherwise and the price is $6k. I'd welcome your thoughts. Thanks!

 

It's more than just plugs.

You also got problematic VCT cam phaser issues too. The 3v 5.4l wasn't one of Ford's best engines.

See if you can't get your hands on a newer truck. Say even with the 3.7l V6. Good engine right there...

 

Look for something with the 4.6 2 valve. Doesn't have the power of a 5.4, but it's reliable and straightforward.

 

What GLC typed is a good option. And, what MF150 typed is true too.
But, don't let that intimidate you. If the engine was taken care of (mainly routine OCL's) you should get BOO KOO miles on the engine before the synchro's start making noise. The plugs, those are a beast of another MOTHER! I have changed them a few times and broke a few. But, I learned from my mistakes! Run a few bottles of TECHRON about 500 miles before the spark plug change. It helps dissolve the carbon on the plug shields. When it comes time to change them, do a bank like this one at a time; heat the engine up, pull the COP's, impact the first 4 plugs out. They will screach like a bag of kittens hitting a wall (It's an analogy; I like cats ). Install those, start the engine again, let it heat up, repeat. Doing it this way virtually eliminates breaking ANY plugs!
BTW, if the truck is in as good shape as you stated, and you like it, BUY IT !

 

just buy the tool for the broken plug removal, I wouldn't worry about any of those trucks and plug change, I have done a lot of them

 

Make sure the engine runs quietly. If there is valve train noise, don't buy it.

 

Thanks! Budget constraints seem to be keeping me in the 04's to 08's for the time being, but I'll keep my eye out for the 3.7 V6 and look into the spec's more closely.

 

glc - thanks for the lead. I've been looking at the threads and spec's on the 4.6 2 valve (glad for the tip about the "W" as the 8th character of the VIN!). The reliability is definitely appealing but it's seems like the towing capacity might be a bit shy for us. Once or twice a month year round we make a Northeast run that's 500 miles round trip with an empty truck and 14' 1000# flatbed on the way down and an additional palletized load of 5000# on the way back with an additional 850# in the bed. It seems like we might be pushing the limits on the 4.6 2-valve. I don't like to go much less than 60 mph on the crowded interstates (65 limit but traffic usually moves around 75 mph). I'd also like the option to haul 2-3 1000# steers in a stock trailer. Thoughts welcome. Thanks again!

 

Thanks, BlueOvalFitter! (I'm not sure if I'm doing these replies right so pardon any mistakes in how this is supposed to be done) Quick question: if I was to buy the truck, would you do the plugs right away or would you wait until there's an issue (or wait to get at least some miles out of it before messing with anything)? Thanks again all!

 

 

The 3.7 wasn't introduced in the F150 till 2011, when they changed all the engines, and it's not suitable for towing heavy. In 04-08 your only choice for towing that much is the 5.4 3 valve.

2004-2008: 4.2 V6, 4.6 2 valve, 5.4 3 valve
2009-2010: 4.6 2 valve, 4.6 3 valve, 5.4 3 valve
2011+: 3.7 V6, 5.0 V8, 3.5 Ecoboost V6

 

HC, ^^^^^^^^THIS!^^^^^^^^
Man, you need to jump on that truck. It sounds like a great deal!
Do the TECHRON additive, borrow/rent/buy the LISLE tool, change the plugs, oil, etc., and pull to your hearts content!

 

I guess I'll be the voice of dissent from most of the others. I'd say if the 5.4L truck made it to 122K, any issues have been addressed. My '08 5.4L F-150 has been great, and about as problem-free as it gets. Other than having to replace an alternator (normal at 130K miles) and recently a passenger exhaust manifold, I haven't had any other "repairs" to make on it (knocks on wood). I did recently have BOTH front springs on the suspension break near the spring perch, but they had 140K miles on them, and were replaced with new Monroe Quick struts. I don't consider that a repair so much since the shocks and springs were all OE and well past their intended lifespan. If you don't hear any cam phaser noise on the '08 you're looking at, and all other maintenance seems to be in-line (other than the spark plug maint) I'd say buy it. I'd take any maintenance items into account with purchase price, so factor in pulleys/belt/spark plugs/shocks/tranny fluid/coolant change/etc. when making your offer.

 

I bought my 07 just a few months ago and was a little worried about all the bad press the 5.4 gets
so I found a cheap one and took a chance
and it was fine when I bought it and 20K miles later it's still fine, it's now got 221000 miles on it.
In fact I'd never even consider a 4.6 again
the 5.4 is the way to go

 

Yeah, 5.4 3v is junk. Why, I even know of one '06 that started knoking at only 417,xxx miles. If I needed it, if a '08 with 122k, only $6,xxx , if no unusual noises,… I'd check maint records as far as I could, change oil and whatever, filters, plugs, and go with it.