Is silicon paste all that different from di-electric grease?

[Buggsy]

I always use to grease my caliper pins with standard lithium grease, but I remember Eric saying this is bad for the rubber bushings. I really don’t know what silicon paste is made of, but I know that di-electric grease is made to be used on rubber and smells like silicon.

So any harm in useing that for my calipers or other rubber parts?

Topic

[gaseousmercury]

Lithium grease is bad for rubber because it is simply petroleum based grease with a lithium complex added to further reduce friction. Dielectric grease and silicone paste are essentially the same thing. Although various additives may be added depending on its intended use (automotive,marine, etc.) they are both made predominantly of silicone; silicone is made from silicone oil and fumed silica. Hope this helps.

[EricTheCarGuy]

There is also a link on the ‘Tools’ page for silicone paste if you have trouble finding it.

[redhorse]

sta-lub markets both at most auto parts stores. the hi temp disc brake grease for pins/backing plate ect. di-electric grease for electrical connection ie;inside spark plug boots ends and/or some elect. connectors.

[redfury]

I bought a nice bottle of it at an auto value store for $25 and haven’t looked back. I’ve been using it like crazy since I found out about from Eric’s videos. No more sticking calipers for me!

[joedirt74]

hey eric what are your thoughts on anti seize i have been using it on caliper pins and such for a long time is silicone paste better?

[thepartsman]

Technically Silicone is the wrong products for metal, just look at the MSDS sheets from GE. It was designed to lubricate rubber parts at a max of 400 degrees and for that job it is perfect, because there are no petroleum distillates in it. On the other hand, when you work with metal to metal applications you need solids to separate the parts as they move, a boundary lubricant. Additionally, when silicone get above 475 degrees, it does something called volatilize (vaporize). The oil begin to disappear and convert back to raw silica, which is actually sand. Technically, when Silicone grease is over heated, it turns into a gritty paste and you really don’t want that between two pieces of metal or on a slide pin in a caliper.

If you are looking at anti-seize you have another problem. The most popular products (typical ones at autoparts store), are more that 60% low temperature mineral oil. To that is added about 30% to 45% calcium fluoride powder (talc like substance) as the thickening agent. Finally, 3% to 5% of copper or aluminum is added to give it color and allow them to call it high quality. Again, when the temperature rises above 400 degrees, the oil begins to evaporate and what is left is a pasty white sticky powder that really is good for nothing. I you want to look at what the OE approves for brakes, check out Ceramlub this web site… CeramicBrakeLube. com Hope this is explains it better….

[dreamer2355]

That was an interesting post there. Thanks for sharing.

[gaseousmercury]

Quoted From thepartsman:

Technically Silicone is the wrong products for metal, just look at the MSDS sheets from GE. It was designed to lubricate rubber parts at a max of 400 degrees and for that job it is perfect, because there are no petroleum distillates in it. On the other hand, when you work with metal to metal applications you need solids to separate the parts as they move, a boundary lubricant. Additionally, when silicone get above 475 degrees, it does something called volatilize (vaporize). The oil begin to disappear and convert back to raw silica, which is actually sand. Technically, when Silicone grease is over heated, it turns into a gritty paste and you really don’t want that between two pieces of metal or on a slide pin in a caliper.

If you are looking at anti-seize you have another problem. The most popular products (typical ones at autoparts store), are more that 60% low temperature mineral oil. To that is added about 30% to 45% calcium fluoride powder (talc like substance) as the thickening agent. Finally, 3% to 5% of copper or aluminum is added to give it color and allow them to call it high quality. Again, when the temperature rises above 400 degrees, the oil begins to evaporate and what is left is a pasty white sticky powder that really is good for nothing. I you want to look at what the OE approves for brakes, check out Ceramlub this web site… CeramicBrakeLube. com Hope this is explains it better….

It is possible to have “silicone grease” still fluid like above these temperatures; it depends on the siloxane utilised for its synthesis as well as the other reafent involved. Some reactions simply use water. this however creates hydrochloric acid and a stiffer less pliable silicone. If some of the original siloxane, usually polydimethylsiloxane is substituited with acetate then you will get a more fluid like and slower curing silicones. These silicones are similar to those in caulking (this is why most caulks have a vinegar like odor)

Also, the silicone doesn’t exactly vaporize per say. It technically vitrifies and forms an amorphous solid that still has some fludiity. This amorphous solid forms a glass like layer on top of the surface. this glass like layer has a lower static and dynamic coefficient of friction and therefore acts like a “dry” lubricant. However don’t confuse this concept with “dry lubricants” as for most of these are usually flurocarbon polymers like teflon.

[gaseousmercury]

Quoted From thepartsman:

Technically Silicone is the wrong products for metal, just look at the MSDS sheets from GE. It was designed to lubricate rubber parts at a max of 400 degrees and for that job it is perfect, because there are no petroleum distillates in it. On the other hand, when you work with metal to metal applications you need solids to separate the parts as they move, a boundary lubricant. Additionally, when silicone get above 475 degrees, it does something called volatilize (vaporize). The oil begin to disappear and convert back to raw silica, which is actually sand. Technically, when Silicone grease is over heated, it turns into a gritty paste and you really don’t want that between two pieces of metal or on a slide pin in a caliper.

If you are looking at anti-seize you have another problem. The most popular products (typical ones at autoparts store), are more that 60% low temperature mineral oil. To that is added about 30% to 45% calcium fluoride powder (talc like substance) as the thickening agent. Finally, 3% to 5% of copper or aluminum is added to give it color and allow them to call it high quality. Again, when the temperature rises above 400 degrees, the oil begins to evaporate and what is left is a pasty white sticky powder that really is good for nothing. I you want to look at what the OE approves for brakes, check out Ceramlub this web site… CeramicBrakeLube. com Hope this is explains it better….

What source are you getting these perncentages from with regard to the anti-seize

[671tamuning]

I use this stuff…I havent had any issues with it. Is this all right?

http://www.permatex.com/products/automo … ormula.htm

[gaseousmercury]

Quoted From 671tamuning:

I use this stuff…I havent had any issues with it. Is this all right?

http://www.permatex.com/products/automo … ormula.htm

I personally have not used Permatex Brand silicone; I use 3M, the same as Eric. I will have to get a can of permatex and try it out. If you haven’t had problems wit it, keep using it. Refresh it when you do your brakes next. Brake Kleen will disolve the residual silicone and grime. Use extreme caution when using Brake Kleen aroud the rubber seals because it will degrade it. Such rubber parts show substantial resistance to the acetone in Brake Kleen. Be safe…..

[671tamuning]

Quoted From gaseousmercury:

I personally have not used Permatex Brand silicone; I use 3M, the same as Eric. I will have to get a can of permatex and try it out. If you haven’t had problems wit it, keep using it. Refresh it when you do your brakes next. Brake Kleen will disolve the residual silicone and grime. Use extreme caution when using Brake Kleen aroud the rubber seals because it will degrade it. Such rubber parts show substantial resistance to the acetone in Brake Kleen. Be safe…..

I use brake cleaner on the metal parts of the brakes only but, thanks for the tip.

I picked the permatex because, I can’t find the 3M stuff anywhere besides amazon so, that’s why I stuck with it.

I get it on discount from pepboys or carquest I can’t remember how much it was but, I know it was less than $10 with tax.

[spelunkerd]

I find this whole thread to be fascinating, and I especially appreciate the knowledgeable post from theparstman. But Ceramlub is not available for retail sale in my city, and evidently it is not widely used by local professionals. There doesn’t seem to be an epidemic of returns for seized sliders, so what is being used seems to be working. And it is mildly suspicious that this is a single product, with most of the supporting documentation available on that corporation’s website. The evidence to support this product seems compelling. But I would be interested in what other manufacturers say about this, in the fairness of giving competing corporations balanced rebuttal time. I would be interested to know what brake lubricants are used for new vehicles from various manufacturers coming off the assembly line. Do those sliders commonly reach 400 deg F? What happens to the adjacent rubber seals at that temperature? What is the cost difference?

[TheArete]

Brake sliders do not commonly reach 400 F, Dot 3 brake fluid starts to boil at around 400 F. The rubber that covers the slide pins would start to melt at those temps especially for models of older cars that were not created using more novel heat resistant formula. Your rotors do indeed get very very hot, way hotter than that even as non-race driver, but the calipers do not directly touch the rotors, the pads do and they act as an insulator and help disperse the heat. In order to create that sort of you heat you need to maintain long periods of braking and to maintain that you need speed. As you brake your momentum is transferred into heat (First law of Thermodynamics) and much of that heat is dispersed at those speeds into the air NOT 100% into the calipers. As high airflow passes over your brakes and rotors it cools the system. Can your caliper reach in excess of those temps… yeah… on track day not during a typical drive, and certainly not enough to warrant going all out and buying new carbon fiber rotors or Ceramic Composites for your daily commute.

That post was fascinating but soundly very suspicious since as you mentioned spelunkerd, there is not an overflow of seized calipers, nor I have I seen corroborating evidence to back up that websites claim. I have personal experience backing the fact that even when using a product for the wrong application (say lithium grease) many times it still will do the trick. I am doubtful that is the “sole” product that should be used. I have 10+ cars in my local family, all of which do their own brake servicing and no failures to speak of using 3m, Loctite, or Permatex caliper lubricants over the past 20+ years. If my immediate death is imminent from not using ceramlub please advise.

Not trying to be mean or spiteful, but I am suspicious when a “brand” is lorded over all the rest as being what should “really be used” and I’d like to hear a rebuttal from someone who deals 3M or Permatex.

[Bad_dude]

The problem is the silicone listed in the tools section shows $17 some thing and click on the link it shows $21 some thing. Price gone up a bit.
I use the sil-glyde I buy from Napa. It’s recommended for brakes and slide pins.

[Author]

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