Brake Fluid.... Why not synthetic ???

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spiderman2000

Brake Fluid.... Why not synthetic ???

Post by spiderman2000 »

Hey everyone !

I have read several postings on the board mentioning not to use synthetic blake fluid, but I was wondering why ? None of the posts go into any detail regarding this, they just state to use standard (non-synthetic) dot-3 fluid. Can anyone answer this question for me? Any good source for the old stuff ??? Every autoparts place I go to sells only the synthetic stuff and it claims to work for any car, but I am concerned about tearing something up.
pope

Re: Brake Fluid.... Why not synthetic ???

Post by pope »

I can guarantee you that every auto parts store you go to has DOT 3 and then may also have DOT 5.
DOT 3 is that standard in the American market for new cars, and is the most available. Dot 4 is a higher boiling point version of Dot 3 and is compatible.

DOT 5 is silicone based and not compatible with the above. You must start with a fresh new system and not just drain the Dot 3 out.

DOT 5.1 is compatible with DOT 3 and uses the same base with a much higher boiling point. Even though you could top off a DOT 3 system with DOT 4 or 5.1, it would make more sense to completely drain the system and then refill.

I am sure that you could get DOT 3 at a 7-11 or the Dollar Store, it is so widely available.

You can use what you want, its just the amount of preparation that it will take to use a new fluid. Its not just plug n play.
mbouse

Re: Brake Fluid.... Why not synthetic ???

Post by mbouse »

spiderman2000 wrote:Every autoparts place I go to sells only the synthetic stuff and it claims to work for any car, but I am concerned about tearing something up.
not meaning to demean or belittle, or make fun... but where do you shop that this is what they tell you? without exaggerating, i am betting that most cars on the road take DOT 3, and not the synthetics.

must be a texas thing, 'eh? i'd have to look for synthetic here, DOT 3 is that prevalent.
spiderman2000

Re: Brake Fluid.... Why not synthetic ???

Post by spiderman2000 »

Ok, ok, let me try to expain..... Maybe its the blond in me coming out....I SURE HOPE NOT, but who knows. What I am seeing is synthetic DOT-3. Maybe I never paid that close of attention to it in the past and its all been synthetic and I never noticed. But every autoparts place I have gone has DOT-3 with the word "SYNTHETIC" in bold print all over the front of the bottle. Oh, and BTW, since you ask I have both Autozone and O'Reilly's close by and thats the only DOT-3 they sell. Maybe I am an idiot and its just a labeling change. :|
mbouse

Re: Brake Fluid.... Why not synthetic ???

Post by mbouse »

:shock:

i gotta look when i get home.
pope

Re: Brake Fluid.... Why not synthetic ???

Post by pope »

That DOT 3 synthetic is compatible with conventional Dot 3. You can add it to your brake system just like it is the old stuff, fully compatible.
pope

Re: Brake Fluid.... Why not synthetic ???

Post by pope »

Use it with no worries!
spiderman2000

Re: Brake Fluid.... Why not synthetic ???

Post by spiderman2000 »

Thanks for the feedback ! :D
So Cal Mark

Re: Brake Fluid.... Why not synthetic ???

Post by So Cal Mark »

the advice against synthetic has to do with moisture accumulation in the fluid and the damage to the entire brake system over time. Synthetic was designed for racing applications where the fluid would be changed often, not left in the system for years
pope

Re: Brake Fluid.... Why not synthetic ???

Post by pope »

Mark,
I think you are thinking of DOT 5 Silicone. It was developed for racing and does not absorb moisture.
The Dot 3 blue synthetic was developed for better compatibility with ABS braking systems. They suggest a flush every 2 years just like conventional Dot 3.
htchevyii
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Re: Brake Fluid.... Why not synthetic ???

Post by htchevyii »

I've been using Valvoline synthetic
http://www.valvoline.com/products/consu ... e-fluid/28
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halg

Re: Brake Fluid.... Why not synthetic ???

Post by halg »

I personally know racers who have taken the synthetic out of their cars because of less pedal feel with the synthetic. This was a few years ago so who knows about today.
Hal
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Re: Brake Fluid.... Why not synthetic ???

Post by Curly »

I don't know if PENRITE products are available in the States, or outside of Oz; but they sell a product called SIN BRAKE FLUID which is a synthetic Dot 4 standard. I've been using it religiously for years (under it's old brand name of "10-10ths") in 3 competition vehicles and our daily drivers, and it stands up to all I can throw at it :D .
Details on website link below.
http://penrite.com.au/pis_pdfs/SIN%20Brake%20Fluid.pdf
So Cal Mark

Re: Brake Fluid.... Why not synthetic ???

Post by So Cal Mark »

the original question was "why not synthetic". I haven't used Dot 3 synthetic, so I'll have to research it.
mbouse

Re: Brake Fluid.... Why not synthetic ???

Post by mbouse »

i just looked at my bottle of NAPA Dot 3 Brake Fluid, purchased last week for my latest project. part # 35-032, in the quart size... the word synthetic is not on the label anywhere.

wonder if you cannot find NON synthetic due to some regional legislation?
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