Do you use any compounds when installing new plug wires? Do you avoid getting compound on the metal connections?

 

Dielectric grease is for metal connections..

Sixto
07 E350 5.4 183K miles

 

Dielectric grease should only go on the outside of an electrical connection... not on the surfaces that make contact so good luck making that happen under a spark plug boot.

 

Silicone/Dielectric on the plug boots (both ends). I apply it with a q-tip. Anti-sieze on the plug threads.

 

Absolutely use the grease.
Every boot, every time, every tune up
Silicone dielectric grease in each boot and take a small pocket screwdriver to distribute the grease inside the boots
Yes it gets all over the metal contact too
Ford used to have us put a dab on the rotor tip during tune ups as well
That used to cause some ugly white corrosion chit on the cap terminals
Ford had us quit using it, and blamed it on radio interference

 

not 100% sure what you’re saying - please clarify.

 

I am saying use the grease

 

I use the grease, but be aware that if you put too much grease in the plug boot when it seals over the plug the heat will cause pressure to rise inside the sealed boot and pushes the boot off the plug. I put the grease on the plug, just a little. Petroleum jelly works just as well.

 

I heard petroleum jelly isn’t good for rubber such as in the boots. Maybe the boots are silicone?

Sixto
07 E350 5.4 183K miles

 

Generally dielectric grease or the silicone equivalent is safe for automotive use. IMHO anything else is either ill-advised or potentially detrimental to any electrical insulation or connector.

Too many "old school" people would indeed use bearing grease or other petroleum products that caused problems over time.