How big is the spark plug gap on a GMC Sierra?
How big is the spark plug gap on a GMC Sierra? I have a 2001 GMC Sierra 1500 C3, cat list .60 gap but every auto store both online & brick and mortar store says .40 is the gap. Most I find, since my truck come with double Platinum plugs, are pre gapped do not gap. Just get a good pair of NGK or champs set to cat recommendation. If it hesitates or if it runs high idle after adjust accordingly. What's the gap on a new spark plug? The new Spark Plug has an Iridium tip instead of the...