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6.0L spark plugs

Discussion in 'Chevy Trucks' started by hairygary, Apr 4, 2010.

  1. hairygary

    hairygary Senior Member
    Messages: 149

    Since i just purchased a new truck, I wanted to change the plugs. I noticed the gaping on the sticker under the hood says .060. However in searching for plugs I have noticed Delco recomends the new iridium plugs, however these plugs come gapped at .040 and you shouldnt regap iridium plugs. I have read reviews on other forums that many people switching to these iridium plugs have been disappointed with a decrease in MPG's. So I was thinking of going with either NGK TR55's (part# 3951) or the Split fire plugs (part # SF524E). Both of these plugs are supposed to be gapped .060 which is the original gap, but are copper and should be replaced every 30K.

    My questions is what is every body else using, I have read alot of good things about the TR55's

    And if GM said orignally the gap should be .060 why are they saying it should now be .040. I have read the TSB about the new plugs, but have also read bad reviews about the iridium plugs.

    just for comparison sake truck is a 02 Chevy 1500hd w/ 6.0
  2. hairygary

    hairygary Senior Member
    Messages: 149

    guess nobody changes there spark plugs.
  3. 2COR517

    2COR517 PlowSite Fanatic
    Messages: 7,115

    I run AC Delco platinums gapped at .040

    Platinum and Iridium are both fine, but make sure the gap is at .040. The smaller gap will give more reliable firing, and help your coils last much longer.

    Hard to beat AC Delco ignition components.
  4. Sydenstricker Landscaping

    Sydenstricker Landscaping PlowSite Veteran
    Messages: 3,882

    I got the AC Delco Iridiums in my 6.0. They were at .60 according to the manual on mine, but I closed them up to .40 and got a little bit better mpgs. I might switch them out for something else to see if my mpgs get a lil better and maybe touch more ooomph.