Thanks bill. I want to confirm that I have the right plugs on my truck. I fear they may be too long. I pulled a couple out last night to see how they're holding up and found the gap was closed! I gapped them all at .35 before install
The information I gave you is what the parts house has listed for your truck.
Closed gap can't be helping your mileage.
Are the rings on the spark plugs? I am pretty sure these use rings but not positive.
After you figure out the rings and if they were correct you need to see if you can put your hands on a bore scope and see what is going on. You may have some carbon deposits or being close to having some serious problems that can be prevented. This is one of those places where an ounce of prevention might prevent a pound of cure.
