The plugs in my '04 are factory original and the truck has 34,000 miles. I have owned it since it had 20,000 miles and have never checked the plugs for tightness. I know the '03-'04 heads have the nine threads per inch. My question is; do you guys think I should check the plugs to see if they are still nice and tight, or just forget about it since I have never had any problems with popping a plug. Truck is bone stock execpt for a Magnaflow catback. She is my daily driver and is babied all the time, execpt when I feel 'the need for speed'.