It can not absorb air if it is in an air free environment. Somebody is going to jump on my dick but if the installation is done properly with quality parts and good workmanship there are no leaks.
"The only advantage to the silicon stuff is it doesn't eat your paintwork." Actually, with all due respect, you're incorrect. It's NOT the only advantage and it's only a secondary advantage at that. The MOST important advantage is that it does NOT absorb water like DOT3 & DOT4 does.
[FONT=helvetica, arial]SILICONE BASED FLUID [/FONT][FONT=helvetica, arial] Fluids containing Silicone are generally used in military type vehicles and because Silicone based fluids will not damage painted surfaces they are also somewhat common in show cars.[/FONT] [FONT=helvetica, arial]Silicone-based fluids are regarded as DOT 5 fluids. They are highly compressible and can give the driver a feeling of a spongy pedal. The higher the brake system temperature the more the compressibility of the fluid and this increases the feeling of a spongy pedal. [/FONT] [FONT=helvetica, arial]Silicone based fluids are non-hydroscopic meaning that they will not absorb or mix with water. When water is present in the brake system it will create a water/fluid/water/fluid situation. Because water boils at approximately 212º F, the ability of the brake system to operate correctly decreases, and the steam created from boiling water adds air to the system. It is important to remember that water may be present in any brake system. Therefore silicone brake fluid lacks the ability to deal with moisture and will dramatically decrease a brake systems performance. [/FONT]
This discussion reminds me of what I tell customers at work when they ask me what the very best cleaning product is to use on their boat. I tell them "Every one of the 200 products on these shelves has people who swear by it and others who swear at it. Sometimes it boils down to if the person used it correctly or not." It is odd that so many of us on here have been using Dot 5 for 10, 20, or more years and love silicone brake fluid, and yet so many others say it is the worst thing to ever come down the pike. Don
Regular brake fluid is a vegetable base hydraulic fluid made up of castor oil and methanol, or it was originally. It was specifically designed to be hygroscopic so water would mix and not freeze. The idea was it would be changed on some regular basis. The aircraft industry banned veg based fluids in the 30s and went to mineral, petroleum based fluid. A lot of old small aircraft had car brake master cylinders but they had to have petroleum compatible rubber parts made up for them. Mixing veg and petroleum fluids creates a terrible mess and destroys the rubber as anyone that has had a Hydroboost go bad can tell you. Rolls Royce had a similar issue because they used Citroen hydraulics but retained the RR traditional servo drum. They had both fluids in the separate systems. Citroens had central hydraulics and they converted from veg based to petro based fluid throughout in the sixties, there were Red Fluid and Green Fluid cars. Red was veg, in which regular brake fluid works. Green was petro and Dexron or MIL-H-5606 will work there. Only problem, they are red. The french ignored or defied the color standard, which was blue for veg and red for petroleum. Purple is phosphate ester. The veg oil was a mistake but it's too late to change now. In a system designed to use it silicone would be the best modern choice. I heard HD changed because bikers would not desist from putting veg brake fluid in there no matter what they said or did. Mixing silicone and veg makes a mess but not as bad as if petroleum got in there. Since the statute of lim has run out I can tell you that when we had a contractor with a backhoe on our property making unwelcome sexual advances on my mother and then got ignorant when she rebuffed him, I put a quart of Skydrol in the hyd fluid tank in his backhoe. I later heard he lost at least twenty grand in downtime and repairs because of that. That was in the early nineties. Mixing incompatible fluids is a no-no-no. Wouldna happened if he had known no means no.
If you have leak with silicone you are going to have a leak with dot 3, dot4 hell even water! The fluid is not the problem. I have had it in my shoebox for 6 years with absolutely NO problems
i read enough bad things about stainless steel lines and silicone b.f. that when i restored my 62 ford galaxie i went with steel lines and regular dot3? brake fluid.this was in 2007,never had aleak !
Ive had both good and bad. Used napa brand in my A sedan and no issues. Used some other brand from the local auto parts store and I've had nothing but issues. Have a spongy pedal, killing my brake light switch, and seeping up the hose where the metal is crimped to the rubber line. No drips but it just seems wet around all the fittings.
True. But it also has a much higher boiling point when fresh compaired to DOT 4 when Fresh. And it always maintains that higher boiling point due to the fact it will not absorb moisture which then lowers the boiling point and causes corrosion inside your parts. In my opinion its a waste of money. DOT4 is more then sufficient for any brake system and even most race cars. Flush it every few years and you will never have a problem. I race super bikes and I use DOT4 in both my race bikes ... and talk about getting your brakes hot. they glow after 20 laps
Looks like it all comes down to WHERE you live and drive. You live in FL, which has an elevation of 300 feet above sea level, max. I drove in Colorado, where I frequently was above 10,000 feet. So, if you do not have to be above 2-3,000 feet, it's probably OK. I just don't want a fluid that has such limitations. Note: I was not the only one with problems at high altitude. Also note that no OEM uses the stuff, or recommends the stuff. BTW, too, I believe that LHM (Citroën 'green' fluid), is mineral based. Dexron is not recommended (but some do use it) for Citroën green systems. Cosmo
You may have hit on something I didn't think of, I AM in Colorado and the altitude might have something to do with this. But, I have used DOT 5 in other Fords with the same brakes here with no leaks at all. Yes, this was a high dollar build and didn't want the paint eaten off. If I knew this was gonna be a big pain in the ass, I would have used dot 3 and a lot of touch up paint!
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