[DeTomaso] DOT-5 Brake fluid myths

Mon Dec 15 13:55:16 EST 2008

no brake fluid is compressible period. 
Dot 5 fluids come in different chemistries  just as dot 3/4/4.5 fluids do. 
silicon based dot 5 fluids as are reccomended in Harley davidson and certain aircraft applications are based on a silicon chemistry and have a specific issue of being able to include a very large amount of dissolved air in the fluid. This is what makes silicon based dot 5 fluids seam to have a spongy pedal feel , To eliminate this the fluid must either be heated during the fill and bleeding process or must be vaccuumed prior and during the fill procedure to ensure that dissolved air is removed. 
most auto brake systems are not compatible with silicon based chemistries and will rapidly deteriorate if these dot 5 fluids are used . There are dot 4 , 4.5 and 5 based fluids that are all glycol based or synthetic non silicon that are compatible with all standard dot 3 compatible systems and extend your wet and dry boiling points well above dot 3 fluids .  for almost all applications the ford , valvoline synthetic in the gold bottle have dot 5 ratings but are glycol ststem compatible. valvoline syntec is only 7 dollars a quart at autozone or oreilys . 

jg

--- On Mon, 12/15/08, Garth Rodericks <garth_rodericks at yahoo.com> wrote:

> From: Garth Rodericks <garth_rodericks at yahoo.com>
> Subject: [DeTomaso] DOT-5 Brake luid
> To: detomaso at realbig.com
> Date: Monday, December 15, 2008, 12:41 PM
> I don't know that DOT 5 Silicon brake fluid is
> "unstable" but it is compressible, which 
> means a soft brake pedal. Silicon fluid is a good choice
> for trailer queen show cars and 
> museum display vehicles because it doesn't absorb
> moisture. But, the compressible 
> nature of the silicon fluid causes a spongy pedal, which is
> fine for a car that's never driven, 
> other than on and off a trailer at shows, it's fine.
>  
> Don't confuse DOT 5 with DOT 5.1 fluid though. DOT 5.1
> is an Ethyl Glycol based fluid like 
> DOT 3 and DOT4 fluid and is suitable for use on a
> street/track driven car.
>  
> ATE Super Blue Racing Brake Fluid ($11.95)
> One of the best values I could find for a high-performance
> brake fluid (536/392 dry/wet 
> boiling point), and only $12 for 33.8 oz. (I ordered from
> www.bavauto.com)  And, the Blue 
> color makes it extremely easy to see when all the old fluid
> is flushed from your system. The 
> same formula also comes in Amber/Gold to make it easy to
> see when all the fluid is flushed 
> from your brake system by alternating colors at each fluid
> flush.
> Blue:
> http://www.tirerack.com/brakes/ate/ate_superblue_fluid.jsp
> Amber:
> http://www.tirerack.com/brakes/ate/ate_type200_amber.jsp
>  
>  
> Here are some of the other fluids I looked at:
>  
>   Brake Fluid    Dry Boiling Point   Wet Boiling
> Point     Price
>   AP SUPER 600        
> 590°F               410°F       
> $18.00/16.9oz
>   CASTROL SRF         
> 590°F               518°F       
> $69.99/33.8oz
>   NEO SUPER DOT 610   
> 610°F               421°F       
> $15.00/12oz
>   MOTUL RACING 600    
> 593°F               420°F       
> $15.00/16.9oz
>   MOTUL DOT 5.1       
> 509°F               365°F       
> $6.50/16.9oz
> **ATE SUPER BLUE      
> 536°F               392°F       
> $11.99/33.8oz**
>   VALVOLINE SYNPOWER  
> 503°F               343°F      
>  $4.97/16.9oz
>   ATE SL              
> 500°F               329°F       
> $7.95/16.9oz
>   CASTROL LMA         
> 450°F               311°F       
> $3.50/16.9oz
>   AP 551              
> 528°F               288°F       
> $12.50/16.9oz
>  *Ford C6AZ-19542-AA   550°F     
>          290°F        $6.95/12oz*
>  
> * Ford Heavy Duty DOT 3 is very inexpensive and is popular
> among racers because of its 
> excellent dry boiling point. It’s considered by many to
> be the best-kept secret in brake 
> fluids.  However, IT ABSORBS MOISTURE QUICKLY! 
> Recommended by Baer and Alcon. 
> According to Hot Rods and Horsepower: "Ford Motor
> Company purchases [Castrol SRF] by
>  the barrel, repackages it, and sells it as Ford Heavy
> Duty fluid to owners of heavy-duty 
> trucks. Although this rumor is often repeated on the
> internet, the two fluids have different 
> specs, so the assertion seems questionable at best. You may
> buy it from your local Ford 
> dealer under part number C6AZ-19542-AA.
>  
> ** ATE Super Blue DOT 4 is even LESS expensive per ounce
> than the Ford Heavy Duty 
> brake fluid, and it ABSORBS MOISTURE SLOWLY!  Note the
> ‘wet’ boiling point - That 
> means better performance under extreme conditions (track
> use or a spirited drive through 
> the twisties). And it’s less likely to cause corrosion in
> your braking system. That’s why I 
> chose the ATE Super Blue (I’ll use Gold when I flush the
> brake fluid again next year). And 
> the alternating color options (Blue and Gold) make it easy
> to tell when you’re done flushing 
> all the old fluid from your brake lines.  Two enthusiastic
> thumbs up!
> Reference:
> http://www.realbig.com/pipermail/detomaso/2008-July/097637.html
>  
> Cheers!
> Garth
> 
> 
>       
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