$1000 spark plug change
Posting Guru
Joined: Aug 2007
Posts: 1,079
Likes: 2
From: Fort Wayne, IN
Really using mileage is a crappy way to tell when maint should be done, engine hours is far better. I have experienced rougher idle at startup, misses and more than normal detonation on modulars at as little as 50k. A plug changed fixed it. However those engines have higher hours for the miles.
As for the 3V plug design, talk about an idiot that designed those. If they would have designed the plug right and machined the lower portion of the plug out of one piece it would have been much better and lead to much less breakage issues. But welding the plug body together coupled with the much longer than need be body and they stick and break. For got it right later in 08' (probably copied the plugs Dodge was using in the hemi) and then axed the engines in a couple years anyway. Bravo.
As for the 3V plug design, talk about an idiot that designed those. If they would have designed the plug right and machined the lower portion of the plug out of one piece it would have been much better and lead to much less breakage issues. But welding the plug body together coupled with the much longer than need be body and they stick and break. For got it right later in 08' (probably copied the plugs Dodge was using in the hemi) and then axed the engines in a couple years anyway. Bravo.
. I used my Expedition as a transport vehicle and as a in field generator, comfort (AC or heat) for long period of idling while going over schematics ect. It was a mobile office. Because of that the 5.4L saw tons and tons of idling. at 91K when I pulled plugs, they were completely shot, horribly. Completely toasted. Saw some mileage increase when I replaced them, as well as more straightforward power (my idling was starting to waver). Check your engine hours if you do alot of work with your truck.
Senior User
Joined: Nov 2011
Posts: 319
Likes: 0
I have a 2008 V10-F350. Has 120k on the clock.
I'm scared to death about these plugs. So... One more time -
If my spark plug boots are certain colt from the factory that should tell me if they installed a one piece or two piece plug right?
What are those colors?
I'm scared to death about these plugs. So... One more time -
If my spark plug boots are certain colt from the factory that should tell me if they installed a one piece or two piece plug right?
What are those colors?
Super Moderator
Joined: Aug 2003
Posts: 25,479
Likes: 742
From: Isanti, MN
Or you could avoid snake oil altogether.
Moderator
Joined: Jul 2011
Posts: 6,515
Likes: 671
From: Sioux Falls Area
seafoam is about the farthest thing from snake oil on the shelves.
lots of them are, but seafoam is not.
lots of them are, but seafoam is not.
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Super Moderator
Joined: Aug 2003
Posts: 25,479
Likes: 742
From: Isanti, MN
I *think* you'll be fine but I'm not sure. Not sure how long engines sit in storage before being installed, but I don't think it's more than a month or two. If that's the case you should have the updated design.
Hotshot
Joined: Mar 2007
Posts: 10,101
Likes: 40
From: Pa
My truck was born in 04/2008
13 bucks a plug . 97000 miles
Senior User
Joined: Dec 2012
Posts: 143
Likes: 0
Just to set the record straight----If you have a 2008, late built 5.4 or a V-10 and you have brown rubber boots that extend from the coil to the plug---you don't have one thing to worry about when it come to changing your plugs. If the boots are black, you could have a problem with them. I changed mine at 115K and it had the brown boots. By the way, I checked the gap of the old plugs I removed, and it was about .065. The factory setting was .041. That much had burned of the platinum plug electrodes in 115K. In my opinion, that's a good enough reason to change your plugs, because wide gaps cause the coil packs to burn prematurely.
Postmaster
Joined: Apr 2008
Posts: 4,724
Likes: 4
From: Rogersville, TN
Some people on here swear by it and others say stay away from it. Personally, I use it on mine. It increases the pressure on the threads, so you have to adjust your torque accodingly so you don't over torque it. I think it is around 10%, which on these plugs is only about a 1 lb difference.