So let me start by saying it's not 100% user error, as I replaced 3.5 ecoboost plugs on my 2013 back in 2015.

I started with the plug closest to the passenger headlight. Removed the 8mm coil screw and tried popping coil off, but no it didn't want to come without me wiggling, twisting, etc. Finally got it.
Then I tried removing the plug with a standard 3/8s rachact with 1 hand, no go. Tried putting 2 hands, 1 close to head and other at end of wrench and still no go..
I said **** it before I broke something. Any one have simliar issue?

2016 3.5 ecoboost with 17k miles tuned (good amount of idle hours and job site putting around)

no problems, just wanted to change them since it's cheap and should be a 1-2-3 done.

 

hm. lefty-loosey right?
shouldn't require massive strength to break them loose. maybe use a penetrating lubricant?

 

Mine came off at 13k miles easily. Try harder

 

Don't know what they should look like but $30 and A hour of my time is worth the change. Old gapped +/-.34 new @.30

 

Why are you changing plugs in a truck with no problems and only 17,000 miles? Am I missing something?

 

Should have re gapped them and put them back in.

 

 

 

People on the forum say to change them at 20k when tuned, so I changed them at 17k. Now other people can see what plugs look like when running MPT prx93 tune @17k. Probably give someone a piece of mind going 30-40k miles on a tune before changing

 

Step up to a 1/2 inch drive with a breaker bar...hopefully you can crack the thread and they're not all like that.