Quick question Brake fluid ??

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Freedom Motorsports

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Just to put it out there, not ALL brake fluids are the same. There are differences, and Amsoil is a synthetic brake fluid designed to higher standards than other brake fluids on the market. I have used it in all of my vehicles for years and I honestly believe it DOES make a difference, especially when resisting fluid break down. I have tested it against other readily available brands to longevity and it beat out Carquest brand, NAPA brand and several others that only truly last a few months before beginning to break down.

For more information click below.

http://www.amsoil.com/storefront/bf3.aspx?zo=1678239
 
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HDRock1

HDRock1

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gpracer1 , good little read

WELL I thought Synthetic was different, apparently it is not.
I guess cuz Synthetic oil is all the rage, they decided to slap the Synthetic label on brake fluid and make me look stupid.
 

Freedom Motorsports

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The key thing to remember when comparing DOT 3 & 4 fluids is the formulation of those fluids. While all that has been said in this thread about the Glycol base of the fluids out there being true for all Dot 3 & 4 fluids, it is the specific formulation of the fluids that causes them to be considered Synthetic. In this particular use of the word Synthetic, it is used to describe the superior performance characteristics of the fluid when compared to the minimum DOT requirements set forth for brake fluid qualifications.

The minimum ("dry": meaning not containing water contamination; "wet": containing water contamination) boiling point according to Federal DOT standards for DOT 3 fluid is "DRY" = 205°C (401°F) : "WET" = 140°C (284°F) and for DOT 4 is DRY 230°C (446°F) : WET 155°C (311°F) and DOT 5 is DRY 260ºC(500º F) : WET 180º(356º F).

When comparing "Synthetic" brake fluids, you must not only look at the fact that they have a Glycol base, but also take into consideration the other ingredient formulation combined with the rated boiling points of those brake fluids.

Amsoil Dot 3 brake fluid has a minimum boiling point of DRY 274°C (525°F) : WET 156°C (313°F) and their DOT 4 fluid has a minimum boiling point of DRY 304°C (580°F) : WET 210°C (410°F).

Amsoil "Synthetic" brake fluid formulation minimum boiling point surpasses the minimum DOT boiling point requirements of even DOT 5 fluid requirements without being a Silicone based fluid. This ensures less viscosity break down of the fluid due to condensation build up in the braking system which means that the fluid is better able to lubricate and protect the braking system better than other brake fluids available.

Yes, using the word synthetic itself may be a little misleading in the fact that the fluid is still a Glycol based fluid as are all other DOT 3 & 4 brake fluids. But like I stated above, it is the other ingredients used and the specific formulation of those ingredients that makes one brake fluid better than another.

If you want to truly compare brake fluids to make sure you use the best available, you must look at the minimum boiling points of the fluids to determine which fluid is going to hold up better for longer so to speak. You will receive better braking performance from a fluid with a higher boiling point.

In the end, not all brake fluids are equal. Hope this helps a little...

---------- Post added at 11:33 AM ---------- Previous post was at 11:22 AM ----------

You can check out the Amsoil Dot 3 Brake Fluid MSDS to read more about the ingredients used in the formulation of the fluid. While not showing the exact formulation as that is proprietary, you can learn more about it for comparison to other brake fluids available.

Amsoil DOT 3 Brake Fluid MSDS
 
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retorq

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From Wiki:
DOT 5 brake fluid is not compatible with anti-lock brake systems.

That right there is all you need to know about DOT 5 ...

I have Prestone DOT 4 synthetic in mine when I flushed the lines, did new braided steel lines, 3/4 master and 3/4 calipers.
 

gpracer1

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Dot 5 is silicone based and is what you see in harleys.
Dot 3,4,5.1 is for normal car stuff.

I used 4 or 5.1 (when I could find it) on my race bike since the temps are much greater when racing.
 

Freedom Motorsports

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From Wiki:

That right there is all you need to know about DOT 5 ...

I have Prestone DOT 4 synthetic in mine when I flushed the lines, did new braided steel lines, 3/4 master and 3/4 calipers.

Just for the sake of putting it out there, according to the Prestone MSDS linked below, (the Prestone MSDS only gives one temperature for boiling point, not differentiating between the wet and dry boiling points.) the boiling point according to the link below is 392°F (200°C), according to that, Prestone DOT 4 fluid does not even meet the minimum DOT requirements for dry or wet boiling points for DOT 4 fluid. Which means you should check your fluid VERY often for discoloration and a burnt smell as it will not last that long at all, and you are at risk for your braking system components failing to perform optimally.

The boiling point is also FAR less than Amsoil.

Prestone DOT 4 MSDS
 

gitrduun

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So is DOT 5.1

DOT 5 is silicone based and does not absorb water, the others are hydroscopic.

I always use dot 4.
Try this read.....
http://www.gomog.com/allmorgan/brakefluids.html

Dot three and four are hyGROscopic actually. I know it's a weird word but that's what it is, just means that It absorbs water, so much infact that it can't be left in open air or it will ruin the fluid
 

gpracer1

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Dot three and four are hyGROscopic actually. I know it's a weird word but that's what it is, just means that It absorbs water, so much infact that it can't be left in open air or it will ruin the fluid

Yep, that's what I meant but the beer wouldn't let me type that :emotions122:
 

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