Bulb grease?

[Westtown Willy]

my trusty Subaru has fried its first bulb, took 10 years & 104k miles but I lost a low beam last week. Stopped by AutoZone for a replacement & the lady asked if I wanted a packet of bulb grease for an extra buck, no idea what she was talking about, she explained that it'll help extend the life of the bulb. I've somehow never heard of this despite having replaced many bulbs over my lifetime, she ended up tossing a packet of the stuff in my bag gratis.

I Googlinated around a bit and read some conflicting things about what it's for and where to apply it, some saying place it on the plastic housing to keep moisture out making sure not to get it on the connectors, while other say apply it directly to the connectors to increase conductivity, wtf?

Anyone here actually know where to apply this slop?

 

[explorerlyon]

I have used it on BMWs, keeps moisture out of the light bulb socket. Spread it around the base of the bulb or completely around the inside of the socket. Put the bulb in and out a couple of times. Bulb grease is the same as dielectric grease you would put on a spark plug boot.

 

[B1Toad]

You put it on your "bulbs" to help them push thru the soil in the Spring.
Seriously though.....
It's just dielectric grease, just put a dab on the contacts and plug it in. It helps keep the moisture from getting in and corroding the contact points and no it won't inhibit current flow, the contact points will push aside the grease and still make contact. The little packages of all that stuff like "bulb grease" and brake pin lube and battery terminal grease are extra moneymakers for the box stores as they only give you a tiny bit so you have to buy it every time. You could just buy a tube of dielectric grease that would last a lifetime and a container of caliper pin slide lube, and there are many products that work on battery terminals.

 

[cliffish]

my trusty Subaru has fried its first bulb, took 10 years & 104k miles but I lost a low beam last week. Stopped by AutoZone for a replacement & the lady asked if I wanted a packet of bulb grease for an extra buck, no idea what she was talking about, she explained that it'll help extend the life of the bulb. I've somehow never heard of this despite having replaced many bulbs over my lifetime, she ended up tossing a packet of the stuff in my bag gratis.

I Googlinated around a bit and read some conflicting things about what it's for and where to apply it, some saying place it on the plastic housing to keep moisture out making sure not to get it on the connectors, while other say apply it directly to the connectors to increase conductivity, wtf?

Anyone here actually know where to apply this slop?

Man I have replaced at least 2 sets on my 2016 outback.

 

[ColoJeep]

The fun thing about "bulb" grease is it turns into heavy tar like substance if you drive on dirt road all the time. If moisture can get into your light housing so can dust.

 

[bucky]

That’s a good employee. Upsell the customer a high markup item. You want an apple pie with that? I just buy a full size tubes/bottles of dielectric, brake quiet and anti seize. Penneys per serving compare to single serving packs and resealable.
I would maybe use dielectric on bulbs if I lived in salt country and I had corrosion issues.

 

[LJBean]

I think the bulb grease is on the same isle as blinker fluid.

 

[Westtown Willy]

You could just buy a tube of dielectric grease that would last a lifetime and a container of caliper pin slide lube, and there are many products that work on battery terminals.

yet somehow I've lived a lifetime without ever using a drop of this stuff & never knew I 'needed' it for bulbs . That little packet the lady gave me looks like it'll last the rest of my life

Anywho, just popped in the new one, lit up just fine with a small blob of this stuff on there. I bought the two pack of bulbs, was about to pop in the other but figured I'll just let it ride until the original dies then swap it, unless I notice some crazy odd difference in brightness of the two then I may toss it in to even things out.

Man I have replaced at least 2 sets on my 2016 outback.

It may be that I don't do a lot of night driving, not a big fan. These things are lit on a very dull roar constantly as 'daytime running lights' though that doesn't seem to take much life out of them.

I think the bulb grease is on the same isle as blinker fluid.

that was literally my first thought when she said 'bulb grease', is this some kinda joke...

 

[LukesfirstJeep]

I've been using bulb/dielectric grease on my dirt bike connectors for years.

 

[Wingback73]

Just so we're all on the same page, dielectric grease is an electrical INSULATOR. It is used on top of connections, in the boot of a spark plug, or even on your already connected battery terminals to keep them from corroding, but it is NOT used on the contacts themselves. So, for example, if you are putting in a bulb, you might smear it around the plastic housing, but it does NOT go on the contact. The primary use is on spark plug boots where we use it to keep water out, allow us to remove the boot from the spark plug, and prevent any sort of arcing.

In the case of a battery, you would connect your wire to the battery THEN put on the dielectic grease; you would not use it on the terminal itself before installing the wire.

d-

 

[Westtown Willy]

Just so we're all on the same page, dielectric grease is an electrical INSULATOR. It is used on top of connections, in the boot of a spark plug, or even on your already connected battery terminals to keep them from corroding, but it is NOT used on the contacts themselves. So, for example, if you are putting in a bulb, you might smear it around the plastic housing, but it does NOT go on the contact. The primary use is on spark plug boots where we use it to keep water out, allow us to remove the boot from the spark plug, and prevent any sort of arcing.

In the case of a battery, you would connect your wire to the battery THEN put on the dielectic grease; you would not use it on the terminal itself before installing the wire.

d-

odd, that's precisely the opposite of what half the internet says , but perhaps more importantly, the instructions that are printed on at least the Permatex brand dielectric grease package which says "coat both parts of the terminal contact with Bulb Grease", which I saw after posting this thread.

What got this thread started was after receiving this packet of the stuff I first Googlinated the topic and was led to this video which says don't put on the contacts; he was of course lambasted in the comments for it leading to a follow up video in which he backtracked

the follow up

so apparently there is no consensus on this topic. I ended up putting it directly on the contacts and around the plastic housing, then plugged it in & it worked so that's good enough for me. I'm thinking as stated in the video that when plugging it in it pushes most of the grease out yielding the necessary metal to metal contact while also piling it up around the outside keeping the moisture out & away from the contacts.

 

[LukesfirstJeep]

I'm thinking as stated in the video that when plugging it in it pushes most of the grease out yielding the necessary metal to metal contact while also piling it up around the outside keeping the moisture out & away from the contacts.

This is exactly what happens. Too much, like many things, isn't good. In my previous life, I was involved with the design and manufacture of electrical connectors, and we did a lot of testing.

 

[B1Toad]

I ended up putting it directly on the contacts and around the plastic housing, then plugged it in & it worked so that's good enough for me. I'm thinking as stated in the video that when plugging it in it pushes most of the grease out yielding the necessary metal to metal contact while also piling it up around the outside keeping the moisture out & away from the contacts.

You are correct, apply sparingly to all surfaces and it pushes aside and fills all air gaps upon assembly while still allowing contact everywhere there would be contact without it. I put it on my battery posts before assembly too, been doing that for a couple decades and never had an issue. If you smear it on afterwards you still have air pockets at the connection point. Apply sparingly before assembly is the correct way. On battery posts I put a little on my fingers and wipe the post, that's it.

There are also conductive greases made but that's a whole different discussion and those greases have very specific uses and can cause problems when used on ordinary connections due to reactions with the dissimilar metal particles contained in the conductive grease products.

 

[Wingback73]

I also followed the directions. I applied a thin coating to my battery terminals to prevent corrosion and then put the connectors on.. According to this thread, I should be fine and have no corrosion and no issues either.

instead I suffered intermittent electrical failures (like whole vehicle shutdown failure, not minor gremlins). I track down every possible root cause, and even bought myself a brand new harness for the vehicle assuming I might have a problem in the physical harness itself. It wasn't until I was discussing it with someone one day, and they asked me if I had used dielectric grease and explained that it was an insulator that I finally went back and checked that. I cleaned the terminals, cleaned the connectors, and everything has been just fine since. With a nice light thin coat on the outside, but not between the two surfaces that are supposed to make contact.

I get that in theory the two metal surfaces will displace the insulator, and make contact. But we should all be really clear that bulb grease is non-conductive, so if we start to have an electrical problem we know where we should look first. The common misconception is that bulb grease, or dielectric, improves electrical connections when the exact opposite is true

 

[Westtown Willy]

The common misconception is that bulb grease, or dielectric, improves electrical connections when the exact opposite is true

I claim no expertise in this area, rather, in the few days since learning there was such as thing as bulb grease I've read and watched a bunch about it & I don't think I've come across anyone claiming it improves electrical connections, rather the claim is that it prevents corrosion which ultimately stops or slows the possibility that your electrical connection will become compromised. Same outcome, different pathway.

 

[OldBuzzard]

I claim no expertise in this area, rather, in the few days since learning there was such as thing as bulb grease I've read and watched a bunch about it & I don't think I've come across anyone claiming it improves electrical connections, rather the claim is that it prevents corrosion which ultimately stops or slows the possibility that your electrical connection will become compromised. Same outcome, different pathway.

Exactly. You don't really need to improve an electrical connection if you have clean contacts touching firmly. Anything you can apply to that contact point won't really improve the conductivity, short of adding gold plating. Keeping the contacts from degrading is what it's all about.

 

[Apparition]

 

[B1Toad]

I can't stand to watch that guy but I'm glad you posted because this video confirms what I suspected, he doesn't know what he's talking about so I'm not missing out on anything by avoiding his videos.
Dielectric grease is not conductive as he says it is multiple times in the video, in fact the meaning of the word "dielectric" is "non-conductive". It can contain an electric field without conducting, in other words it's an insulator.

 

[Apparition]

I can't stand to watch that guy but I'm glad you posted because this video confirms what I suspected, he doesn't know what he's talking about so I'm not missing out on anything by avoiding his videos.
Dielectric grease is not conductive as he says it is multiple times in the video, in fact the meaning of the word "dielectric" is "non-conductive". It can contain an electric field without conducting, in other words it's an insulator.

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I’m not a fan of his either. I searched for dielectric grease in auto applications.

There is conductive grease out there but I agree that dielectric isn’t.

However he’s doing what I’ve always done. If replacing spark plugs and such I fill the wire with dielectric grease and then shove it in the plug.

 

[sab]

I also followed the directions. I applied a thin coating to my battery terminals to prevent corrosion and then put the connectors on.. According to this thread, I should be fine and have no corrosion and no issues either.

instead I suffered intermittent electrical failures (like whole vehicle shutdown failure, not minor gremlins). I track down every possible root cause, and even bought myself a brand new harness for the vehicle assuming I might have a problem in the physical harness itself. It wasn't until I was discussing it with someone one day, and they asked me if I had used dielectric grease and explained that it was an insulator that I finally went back and checked that. I cleaned the terminals, cleaned the connectors, and everything has been just fine since. With a nice light thin coat on the outside, but not between the two surfaces that are supposed to make contact.

I have just a little bit left of a large tube of dielectric grease that I bought about 30 years ago. In other words, I've used a lot of it. I've known that dieletric grease is non-conductive for at least that long, and I was taught by well-seasoned, highly-qualified techs to apply it directly into the contacts of connectors that you don't want to corrode due to water intrusion. It's only purposes are to prevent corrosion and to prevent voltage loss between connectors. In all these years, I've never experienced a situation where the dielectric grease prevented electrical transfer from pin to socket in a connector junction.

The grease doesn't have enough shear strength to prevent metal-to-metal contact. I think you were experiencing another problem, like a slightly loose battery terminal that was inadvertently fixed in your search for a solution. There are more than one threads on this forum where a slightly loose battery connection vexed the TJ owner for considerable amount of time until it was discovered...