changing brake fluid?

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Jun 27, 2007 | 07:54 PM

wannafbody

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changing brake fluid?

I've siphoned the brake fluid out of the plastic resevoir and then filled with new fluid. Is this an effective method of replacing the brake fluid(multiple times) without the hassle and risk of bleeding and possibly getting air in the system?

Jun 27, 2007 | 08:44 PM

VIP1

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From: Eastern MA

No, replacing the fluid in the reservoir is only step one. You still need to bleed the system until new fluid flows out of the bleeder screws at all four wheels (don't let the reservoir run dry though and make sure its full when complete). Otherwise you are only doing half the job.

And what do you mean by "multiple times"? Did you change the fluid in the reservoir multiple times without bleeding? If so, unfortunately you aren't accomplishing much.

Jun 27, 2007 | 08:54 PM

wannafbody

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Ya, twice. I'll have to bleed them completely sometime when I have some help. The fluid doesn't look too discolored and the brakes seem to work fine.

Jun 28, 2007 | 04:06 AM

waldershrek

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Yeah sadly you haven't accomplished much other than changing the fluid in the reservoir.

Jun 28, 2007 | 02:29 PM

pwrtrip75

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Just out of curiousity why would you change the brake fluid? Especially in this new of cars? Seems like changing the air in the tires to me.

Jun 28, 2007 | 03:43 PM

z28bryan

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Well at least for racing, the stock brake fluid has a crappy boiling point. I would also change the fluid to ATE or something for the street as well for better assurance.

Jun 28, 2007 | 07:08 PM

VIP1

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From: Eastern MA

Quote:

Originally Posted by pwrtrip75

Just out of curiousity why would you change the brake fluid? Especially in this new of cars? Seems like changing the air in the tires to me.

Brake fluid doesn't last forever. It absorbs water (even from the air, this is intentional, otherwise you'd get ice in the lines on a cold day) and gets contaminated with particulates. With this contamination and the hot/cold cycling it becomes less effective in its operation (squishy pedal, lower boiling point, and some decrease in stopping ability -- less bite on tip-in)

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Jul 3, 2007 | 01:13 PM

1 FMF

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From: CT

Quote:

Originally Posted by pwrtrip75

Just out of curiousity why would you change the brake fluid? Especially in this new of cars? Seems like changing the air in the tires to me.

if you do a web search, you can find a lot of reliable info on reasons why to change/flush brake fluid. It's recommended to do it every 1 or 2 years.

Brake fluid absorbs water. Over time you will get water in the system, and it ends up corroding/rusting the inside of the calipers, requiring new calipers. Flushing the brakes periodically is good preventative maintenance, especially considering dot3 is very cheap.

I just did new rotors on my car and flushed my brakes for the first time, 2002 ss with 37k miles. The color of the brake fluid out the rear calipers was black and nasty. That doesn't mean the brakes won't work, but they will fail and require maintenance/repair sooner than later if the brake fluid in the calipers get contaminated with water/moisture or dirt/dust. The caliper piston seals will also fail sooner.