High mile spark plug change
 

I have 01' Screw 4.6 that I've had 4yrs. It just hit 140k and I want to do a plug change with new oem coils. Truck runs fine but I'm unsure if the previous owner ever changed them. My concern is that there are two new oem coils on #1 and #4. I'm not sure if they we're replaced do to failure or spitting a plug. I just don't want to pull a plug that had the threads repaired. You probably can't tell either by looking down the plug well can you?

I've done three plug changes on F150s in the past 10 years with no worries until I start reading theses horror stories.

Worst case you will have to Timesert or Bigsert the holes.

I went through all the service records I got with the truck last night. This truck was always maintained by the Ford dealer. I found that all 8 plugs were replaced at 53k and the number 1 cylinder had a misfire at 113k so a new coil corrected that problem. But there's no paperwork on #4 on whys its new. Since I bought the truck the original owner has moved out of state so asking is out.

Well I got all 8 plugs changed with no issues today. The ford dealer that changed them at 53k had the plugs torqued 24-28 ft lbs. (which is the reason I never spit a plug with in a 100k I guess) I torqued the new plugs to 24ft lbs. I'll recheck the torque this spring

When I replaced mine recently I just hand tightened them to where I couldn't go any further without stripping :0 is that ok since I don't have any air tools?

You don't need air tools, you need a torque wrench so you know exactly how tight they are. The need to be 28 ft. Lbs. to keep them from spitting out.

I have a small inch lb torque wrench I used. Fits good when torquing the rear plugs.
You didn't use anti seize did you?

I know some will say to use anti seize and some will not. The same with how tight the plugs should be. I'll tell you the plugs I changed in my truck had no anti seize and were torqued to at least 24-28ftlbs. And I went 100k without spitting a plug. And they were all still really tight.

Fellas -

Read FAQ's # 51 & 52 here:

http://www.blownoutsparkplug.com/


MGD

PS: if using nickel-coated plugs, no a/s is required. If you DO use a/s you MUST adjust yer torque values downward, as explained here:

http://densoiridium.com/installationguide.php

I replaced my plugs at 119k miles. I used anti-seize and torqued them without using a torque wrench just using my judgment. Now, it is at 132k miles with no issues so far. I'm retiring this week so I will check to make sure they are still tight and let everyone know.

Congrats on the retirement!

It seems from what I've been reading some get away with what you did and some do not. Definitely report back with your findings. I plan on checking mine in a few months just to be sure. I would rather spend an hour checking them then hours and $$$ fixing it...