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The Big Money
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How often should you replace the brake fluid in your system? I think mine was last changed 10 years ago and is feeling a little sluggish with alot of pedal travel. Whats the best step by step way to replace brake fluid?
 

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Race it, Don't rice it!
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Brake fliud absorbs water from the air very quickly.

Change it as often as needed. Here in the midwest, every wo or three years.

A pressure bleeder works faster but the old pump and hold works too.
 

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I have a turkey baster that I use to get all the old fluid out of the res. I then fill it back with fluid and bleed until I get clean fluid out. I use a vacuum bleeder that I made from a $14 Harbor Freight venturi vacuum pump, some hose, and a spaghetti jar. It goes quite quickly.

Every 2-3 years is good for most cases. Brake fluid turns from clear (new) to yellow (getting old) to brown (too old) as it absorbers moisture. If you push your car very hard once a year would do you better. Remember as the moisture content of brake fluid goes up the boiling point goes down.
 

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One of the reasons Mercedes has such a great record for reliability is the suggested maintenance schedule. Brake fluid is flushed with new at 10,000 mile intervals!

I'm thinking of changing to a synthetic fluid to eliminate the moisture absorbing properties of DOT3 fluid, but there are so many opinions that condemn the change I'm procrastinating. :confused:
 

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Tominator said:
I'm thinking of changing to a synthetic fluid to eliminate the moisture absorbing properties of DOT3 fluid, but there are so many opinions that condemn the change I'm procrastinating. :confused:
IMO the only reason to go to DOT5 (silicon based and non-hygroscopic like normal DOT3 & 4) is for a show car that rarely (if ever) gets driven...and half the reason would be just to keep from the DOT3 stuff messing up the paint. I would suggest you look at something like the Castrol LMA (Low Moisture Absorption) first for something that gets driven.

Edit:shoot...looks like LMA actually stands for Low Moisture Acitvity...Absorption would have made more sense. :rolleyes:

Another fluid to look for is ATE TYP 200. It is the same as the Super Blue stuff but amber colored instead. The blue stuff can stain plastic reservoirs. The reason for the different colors is so you can tell when you are done bleeding. Use the TYP 200 one time and the Super Blue the next. I have heard that it also absorbs moisture slowly and it also has a higher dry and wet boiling point while still only being about $12/L
 

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IF for what ever reason you decide to try silicone brake fluid, be aware that ALL of the rubber seals in the MC and wheel cylinders will need to be changed out for new and dry pieces plus any rubber hoses. The entire brake system will have to be totally purged with alcohol then new silicone brake fluid and then filled. Silicone brake fluid, while it doesn't absorb water easily will (probably) cause you to have a spongy brake pedal and will increase braking effort. I speak from an expensive experience on a past car. Advice given in the above posts is good - use a good DOT 3 or 4 brake fluid. I'm using the Super Blue Racing for the high temp capability(535 deg F) as well as lower water absorption for my 4 wheel disc brake system. They recommend change out in 2 to 3 years for a daily driver.
 
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