One thing for sure with the advent of duelies the temp in the chamber has risen. Might be the newer plug types were needed to keep from melting.
I just changed the plugs and wires on the wifes suburban after 108,000 miles and the plugs were still running good. I had never pulled them to give a look. The gap was about .065. They were NGK's from the factory 10 bucks each...I opted for the much cheaper replacements. I came near putting them back in like they came out but went ahead and spent the money.. prolly wasted it!
Big JIm
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