June 22, 2011on my 03 4.8L i used E3 plugs and MSD super conductor wires and gained a little over 1mpg. i just passed 86,000 on my 06 and should probably change them on this one.
Forums : Silverado (c/k) (1999 - 2006) : Plugs & wires (5468 Views)
Subscribers : 05SilvyZ71
June 22, 2011i would avoid e3,s your gain cam from the msd more that likely. e3`s suck.trust me.put it on a computer and count the misfires.
2000, GMC 2500 6.0L 4L80E, 4.10, Black Bear tune.
August 4, 2012I just replaced My Plugs with AC Delco Iridiums and replaced the Cables. The Plugs came with a 0.40 Gap. At Pep Boys they told Me the Correct Gap for My 2001 2500HD 6.0 Engine is 0.40 Gap.
As I was installing the Plugs I found a Tag under the Hood that said Gap is 0.60.My Manuel says o.60.
As I pulled the old plugs I checked the Gaps and they were all 0.40. They had been installed at 80,000 miles. I now have 140,000 on it.
My Question is what is the Correct Gap and what could be the damage by using the wrong gap?