Here in Texas where everything rusts and corrodes I use it on all exterior light bulb sockets. I miss Utah where nothing rusts because there is no humidity. Anywhere else only if there is an issue.

Hi Bruce I’m sure you know that dialectric grease is non conductive and should only be applied to a nice, shiny, dry and clean connection, after it has been screwed tight. And only in places where weather ( or more to the point, moisture) can affect the connection. For instance, ground wire connections under the car from the engine to the frame. There is never an application for it inside the car, where it does not get wet. Many folks erroneously think that it is applied the the connection before it is screwed together.
also, I would never put it anywhere near the top of the spark plug and then attach the boot. You are degrading the performance of the plug. They need a nice dry clean and tight connection. Again, dialectric grease is non- conductive.

I use it on spark plug coil boots and o rings. It’s a good lube for most o rings and won’t degrade the rubber or plastic. After I learned it was non conductive I don’t use it on the contacts of electrical connections any more.

Ugh! Horrible stuff. Hard to get it off. Migrates into areas you don’t want to on your hands and tools. Residue leaves fish eyes on new paint, buggers up otherwise well detailed paint, permanently stains upholstery. Went into the chemical recicling many years ago.

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