^ you can add O2 sensors to that list also.

 

A little bit of KY, some contortionist maneuvers, and a lotta luck!

I have tried iridium plugs before, it's all in your head... I felt no difference.

 

Spark plugs are one of those things that can only make your truck run the same or worse than stock. No improvement.

 

Well, not necessarily, especially if the old plugs are worn

But FWIW, I experimented with the factory platinum plugs, Denso iridium plugs, and NGK copper TR55's, and my truck ran exactly the same with all 3 ...and, the factory plugs were gapped inconsistently between .045 and .065 (should be .060 for the factory platinums)

 

That's my point...... Plugs wear out, you put new ones in. Bam! Same as stock original power....

My other point is that these are 100,000 mile plugs. As long as they are firing, the truck runs the same. No improvement changing them early.