Anyway the stock plugs lasted 200k
#11
Mark
iTrader: (1)
Ha.. Me too
#14
Senior Member
I don't see why they couldn't last for the life of the vehicule.
Most of the time sparkplug are changed because while looking at them, you already have the new one, so put them in, but the old one was still very good.
but in the 5,4, it's not the time they would last, but how hard will they be to replace when you'll really need to.
And one you have them cranked out, I would be worried about them been weakened a bit..so new one in!
I replaced mine last year, and they were still looking #1 and no issue at all. (put new one for the previous reason.)
Most of the time sparkplug are changed because while looking at them, you already have the new one, so put them in, but the old one was still very good.
but in the 5,4, it's not the time they would last, but how hard will they be to replace when you'll really need to.
And one you have them cranked out, I would be worried about them been weakened a bit..so new one in!
I replaced mine last year, and they were still looking #1 and no issue at all. (put new one for the previous reason.)
#16
Brought my truck to the shop and got the plugs changed Monday. They said they broke all 8 but now the new ones are in and good to go truck runs way smother and I think my mpg has increased too
#17
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majerus (08-21-2015)
#20
TOTM 8/2019
I changed mine on my 2006 5.4L when it hit 105k. And this really wasn't because I wanted to, the truck was misfiring and shuddering all over the place. I probably would have not changed them if the truck ran good. Changed them out and it runs like a beast now, my plugs were really beat though when I pulled them out, covered in carbon.
Oh yeah, and I broke all 8, had tons of debris fall into the cylinders too. For peace of mind I had the truck taken to the dealer to have them bore scope each cylinder and vacuum/blow all debris out. Wasn't fun, or cheap. I'd recommend if you do them yourself, to not crank the Lisle tool to far down in there(that's what I did and the tool actually broke electrodes pieces into the cylinder's when the threaded rod pushed the porcelain down).
But it runs good now!
Oh yeah, and I broke all 8, had tons of debris fall into the cylinders too. For peace of mind I had the truck taken to the dealer to have them bore scope each cylinder and vacuum/blow all debris out. Wasn't fun, or cheap. I'd recommend if you do them yourself, to not crank the Lisle tool to far down in there(that's what I did and the tool actually broke electrodes pieces into the cylinder's when the threaded rod pushed the porcelain down).
But it runs good now!