I have searched through my owners manual and my scheduled maintence book on my Ranger and I cannot find the recommened amount of K. Thats recommended for changing out the sparkplugs in my truck. Does anybody know what the right amount of K is recmommeded for changing out spark plugs?

__________________
http://www.threadbombing.com/details.php?image_id=1688

I usually do them 40-50k, they can last longer though. Make sure you check out Advance auto parts online, they run promos from time to time and I got all 6 Motorcraft plugs for 20.00 shipped so stock up!