Spark plugs

[fuzzie]

 

I have an 04 Silverado 2500 6.0L For the hell of it I pulled 4 plugs and checked the gap (plugs are original) the gap ranged from 0.45 to 0.65, looked in the owner's manuel and it said gap should be at 0.40. (nothing on the sticker)I heard that these are not a gapable plug....didn't check the part # on the plug. Should I replace these plugs and what is the proper gap.

[Metz Motorsports]

The plugs are probably worn making the gap bigger. They probably need replaced. Just my 2 cent.