Plug Gap Question for '07 LC9

[Folically Challengjed]

Since it seems like they've got my oil consumption "issue" fixed, it looks like I'm going to keep my '07 Yukon XL. And since I'm nearing 102K miles, I'm treating it to new plugs & wires.

 

I pulled a plug, and it was labeled, "41-985". I've been told by a dealer & an AC Delco sales outlet, that this plug has been superseded by 41-110. So, I'm now the proud owner of 8 of the latter.

 

I'm reading that these 41-110 plugs are supposed to come to me already gapped at .040. However, I just checked them & found 3 at .036, 2 at .037, and 3 at .038. Which leads me to some questions for those in the know:

 

1) Could the discrepancies between them just be due to my cheap-a$$, made-in-china, disk type gap checker, and/or my mis-reading of it?

2) Am I nuts for having expected the plugs to all be gapped the same?

3) Should I just quit worrying & throw them in the engine, since it won't make darned bit of difference in how the truck runs? Or,

4) Should I go against the laws of the universe and try to open the gap of all of these iridium plugs to .040 (doing so, of course, by pulling gently on the outside edges of the tip, and never, NEVER prying upward from anywhere near the electrode)?

 

Thanks in advance,

 

FC

[elite0259]

I just did mine at 102k also. I just threw em in, didn't even check the gaps, they're working great.

[Folically Challengjed]

Got 'er done. I went ahead & gently adjusted the gap to .040, & the tips looked fine when I was done. I'm quite proud of myself for even getting the back one out on the passenger side, with only 1 extra trip to the parts store. Turns out my extension was too long to allow the wrench head to get back in there. I was also kind of surprised at how easily they came out. Then again, when they had to take it apart a few times to fix the oil consumption, they had to have had them out a time or two already.

So, here's the one from the cylinder nearest the radiator on the driver's side, with a new one. Not too bad for 101.5K:

Here's all 8 together. With as much oil as this thing burned for the first 75K, I wasn't expecting them to look this good. (Note: 2 had been replaced when they were broken off during when the heads were replaced. I didn't keep track of which ones they were, but they were 41-110's, but the rest were 41-985's.)

And, only 1 plug wire had any issues.

On the plus side, the new 748RR wires seem to be thicker than the old ones. Maybe 8mm vs. 7mm? In any case, it starts & idles beautifully.

FC