well my 2004 f150 supercrew just turned over 300k last nite.still runs great . never had any major problems and still running the original spark plugs from the factory. Engine has never had any skips or hesitations. gas mileage is between 15 and 19 mpg.

 

Good Job! Somewhere I read that these trucks are garbage. HMMM LOL

 

id do your plugs and you may be running like new...

 

Would be the first reported 300k plug change!

 

....

4.6 or 5.4?

300K on factory plugs?

What gas do you use?

 

running 87 octane sunoco and irving fuel . 5.4 . plan on changing plugs this summer. hopefully they will not break ! May not be much carbon build up as I run 4-5 hours straight on the highway. I would say 98 % of my driving is extended highway driving.

 

Pretty amazing!

 

That is amazing, but I'd still bet that 6 of 8 plus break off if you've never changed them in 300k miles, lol

 

That's awesome. Best of luck to you on the plug change. It might bring up issues with other things when they are replaced though.

 

I almost swallowed my false teeth when I read that.... and I don't have false teeth! You MUST post pictures of the plugs when you do change 'em. Hard to imagine there's anything for the spark to jump to. The miles you drive (and how driven) are the only way possible to achieve that feat.

 

You may be surprised. There used to be a regular on here several years ago that drove a Gov't. supplied FX-4. An '05 that he put 120K+ on in 22 months. He totalled it on an offroad pursuit but had changed the plugs at a little over 100K. mi. He posted pictures of them and with no problem extracting any of them, they had virtually no rust or carbon that is typical of these 5.4L 3V engines. I'm sure that he may have been using top tier gas, but the primary reason for the pristine appearance was the fact the engine never had a chance to cool off or produce condensation.

 

Thanks! ..... 300K miles is awesome ..... please do post pics of old plugs here when done ..... just freekin' awesome I tell ya!

 

We put almost all highway miles on our trucks. Like the OP we tend to drive 100+ mile at a time. My plugs @ 100k always look pretty good. Not exactly new but nowhere near worn out.

We had a 2005 that went 165k on its first plug change. It would barely climb a hill and it had almost no power. The plugs that came out of it we were worn worse than any I have ever seen.

But like all of ours to date, they came right out no problems. I've yet to have a plug break off.

300k? WOW! I'd like to see those spark plugs. In fact I'd be happy to install a new set just to see them. Bring the truck over when you're ready. Parts store is about two blocks from my place.

 

@ Voo, sure i'll bring it over to you. I'll even bring my own plugs , purchased them about 200k miles ago,lol. what was you address again ??

 

Congratulations!...I am very jealous. You will probably get another 300,000 out of it. Want to trade?