Headlights last longer with dielectric grease?

[glen richards]

I was told by my parts guy that because higher intensity headlight bulbs burn hotter when you use dielectric grease on the electrical connections they they last longer. I just replaced mine and did not use any grease so I plan to pull the connections anyway, but has anybody found that they do indeed last longer?

Topic

[Aaron]

Honestly what they said doesn’t make sense as far as the reasoning. Dielectric grease will help keep water out (most headlights are inside a waterproof housing anyhow) and sometimes as it gets old will gunk things up so it’s done more harm than good.

Personally I don’t use it on light bulbs. I do use it on things like spark plug boots as it can help you remove them later without breaking the wires.

[Lorrin Barth]

I’d guess it will be kinda hard to ever know the answer. My car is elven years old and I have never touched the headlights. If after eleven years a headlight goes out could we attribute it to a lack of silicon grease?

Maybe what the parts guy meant was that silicon grease in the connector would keep out water making the connector last longer.

I wouldn’t just go dabbing it anywhere. Silicon grease isn’t recommended for pin type connectors.

[Paul]

I might be completely wrong, but my reasoning: If the dielectric grease is electrically-impeding the connection, then less current should flow through the bulb, and therefore the bulb should run cooler – i.e. no/neglible current is flowing through the dielectric grease, so it shouldn’t raise the temperature of the connection due to resistive heating.

[Bob]

I use dielctric grease on lamp bases to reduce corrosion and make them easier to change later. I hate fishing out parts of broken light bulbs. I used to use Vaseline on boat trailer lamps but went to the silicone stuff because I got tired of my (adult) kids making jokes about the jar of Vaseline in my tool box.

I have not had a problem with the grease screwing up contact between the socket and the lamp.

[EricTheCarGuy]

It might reduce corrosion, if there is any, most bulbs and connections are sealed these days. As for making them last longer, not likely. If anything, it will just make a mess. If it makes you feel better, go for it.

[Bryan Carter]

Headlight bulb lifespan is dependent on several factors, and none of them really have to do with dielectric grease.

For an HID setup, the number of times the light is cycled on and off shortens the lifespan more than actual runtime. Most of the stress an HID bulb sees is during the initial striking of the arc. So if you want to extend HID life, limit the number of times you turn the lights on and off.

For a standard halogen bulb, total runtime is the killer. Halogen bulbs (like many opinionated people on cable news) give off far more heat than light. The entire time a halogen bulb is at operating temperature, it’s slowly evaporating trace amounts of it’s tungsten filament. Once the filament gets too thin…pop! Game over. So the only way to extend halogen life is to run the bulb cooler (less voltage), or not use it at all.

[Author]

Replies