My 2002 silverado with the 8.1 has 85k (bought it new)on it, and misses while under heavy load/acceleration. I want to install new plugs, so naturally I want the best. The Chevy dealer wants $275 for OEP, so now I am looking elsewhere. I found a site called sparkplugs.com. that has a variety of brands and quality, to name a few: Denso Iradium $11.99, Autolite XP $6.40, Champ $8.95, NGK $8.95 and NGK-IX $7.32. The most expensive would be less than a C note, Sure sounds better than $275. I think the truck was delivered and still has Delco. Note they do not offer Delco.So I was wondering if anyone has used any of the plugs mentioned and what kind of service you got from them? I am really impressed by the long milage I have gotten, and that is what I am looking for now in a new set of plugs.

 

I used Autolite XP Iradium for my 2001 5.3 engine. I can't tell the difference. Seems to be OK.