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You should be able to make your own adapter by getting another cap for your master cylinder reservoir.
Changing brake fluid?
- Thread starter Back40
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I've cranked right down on it on both my F-150 and Neon. Never had a problem with the reservoir. You just have to make sure it's centered... Of course I have the euro adapter for my VW's... Only one I haven't figured out how to use it on is my wife's MG Midget. The cap is about 3" across on that one.
..you are rebuilding calipers, we are changing fluid, think about it.
I did the brakes on my 'lil cousin's 97 Mitsu, the fluid came out rusty and the rust would collect around a magnet applied to the jar. I pressed the piston as far back as possible in order to remove all the fluid I could, seemed like a good idea.
[ June 01, 2004, 11:55 PM: Message edited by: Audi Junkie ]
I'm almost 50 years old and have went through a whole lot of cars in my life time and have NEVER changed brake fluid and have never had any type of related failures either.
I did have an old Buick Regal needed a new master cylinder but the car went 350k miles and things like that are expected.
Now that I know it should be changed and I see that the vast majority of people here agree it should be changed I WILL also do so. However I do wonder if two or three years might be a bit sooner than whats really needed.
I haven't even checked my owners manuels on this but will do so this morning.
After learning here I'm taking great care of my cars engine oil, Trans fluid and cooling system so I might as well do the brakes too. Do it all right.
I did have an old Buick Regal needed a new master cylinder but the car went 350k miles and things like that are expected.
Now that I know it should be changed and I see that the vast majority of people here agree it should be changed I WILL also do so. However I do wonder if two or three years might be a bit sooner than whats really needed.
I haven't even checked my owners manuels on this but will do so this morning.
After learning here I'm taking great care of my cars engine oil, Trans fluid and cooling system so I might as well do the brakes too. Do it all right.
Kestas
Staff member
Hankrr, where do you live? (which climate?) I'm almost 50 years old and I've had lots of problems with corrosion in the brake hydraulics. Climate can have a significant effect on brake hydraulics.
Don't expect your owners manual to mention anything about preventive brake maintenance. Only the european manufacturers address this issue and recommend exchanging the brake fluid every two years.
Don't expect your owners manual to mention anything about preventive brake maintenance. Only the european manufacturers address this issue and recommend exchanging the brake fluid every two years.
Here are a few places I've already posted my thoughts;
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=16;t=000715
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=16;t=000724
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=16;t=000924
As to the area past the seal, I've only seen corrosion here where brake fluid has started leaking past the pressure seal then absorbing a full load of water and corroding the bore or in cases where the dust seal has failed from heat or age. The pressure seal will live longer in fresh fluid. The dust seal should be inspected with every pad change and replaced if showing signs of deterioration.
It really comes down to this;
Brake fluid absorbs water and salt through seals, hoses, and other plastic parts and becomes corrosive and more compressible as this happens. Because of this, it should be changed at least every couple of years.
Just because a manufacturer does not specifically recommend something does not mean it should not be done. I've owned several cars with no ATF interval recommended, that does not mean you should not change it. This forum is all about getting maximum life, reliability, and performance from automobile systems. For the brake system, as well as all other fluid filled systems on the vehicle, that means changing the fluid occasionlly.
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=16;t=000715
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=16;t=000724
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=16;t=000924
As to the area past the seal, I've only seen corrosion here where brake fluid has started leaking past the pressure seal then absorbing a full load of water and corroding the bore or in cases where the dust seal has failed from heat or age. The pressure seal will live longer in fresh fluid. The dust seal should be inspected with every pad change and replaced if showing signs of deterioration.
It really comes down to this;
Brake fluid absorbs water and salt through seals, hoses, and other plastic parts and becomes corrosive and more compressible as this happens. Because of this, it should be changed at least every couple of years.
Just because a manufacturer does not specifically recommend something does not mean it should not be done. I've owned several cars with no ATF interval recommended, that does not mean you should not change it. This forum is all about getting maximum life, reliability, and performance from automobile systems. For the brake system, as well as all other fluid filled systems on the vehicle, that means changing the fluid occasionlly.
I thought it was about making informed decisions based on the facts. The fact is, changing the brakefluid does very little to extend the life of brake conpenents or improve preformance. It seems to me like it is a recently discovered way for the European manfacturers to extract more dollars from their customers.
Well, I am no engineer, but I looked around and found this.
Corrosion of brake fluid from depletion of additives
They are saying that the moisture problem is minimal but the fluid should be changed anyway because the corrosion is being caused by copper. I had never heard of this and you guys are welcome to tear into this.
All I know is I am not driving around in something where the whole engine compartment is spanking clean but the reservoir shows a bluish cloudy goo.
Corrosion of brake fluid from depletion of additives
They are saying that the moisture problem is minimal but the fluid should be changed anyway because the corrosion is being caused by copper. I had never heard of this and you guys are welcome to tear into this.
I don't know about you, but I like the pedal feel that I get with freshly bled breaks.
Honestly, it's mentality like this that allows people like my cousins (with their suburban) to look at the brake fluid resevior, see that it's completely full with black fluid and have the brakes compress to the floor before any braking happens (literally) and say everything is fine.
Admit it. Brake fluid does occasionally need to be changed. I've seen many a 2-5 year old cars with spongy brake pedals. They need to be blead. It will affect braking performance if there is a different amount of water and air in each of the lines.
Good post. Light, not heat. The figures 2 and 3 clearly shows the corrosion of the piston occurs mostly on the part of the piston no longer in contact with the circulating fluid, beyond what they called the flat cut ring, at least later in the life of a set of pads. What I have seen is more the outside than the middle, but that could be due to wear of the plating from the seal in this case.
Too bad they gave no indication of how long it takes the copper levels to become destructively high. You lose a lot of brake fluid on every rebuild/replace. I still suspect if you are changing the rubber parts before trouble occurs, the brake fluid will be gone before it goes bad. The more I think about this, the more I think it is better to rebuild in a timely manner, than replace. That way I know the piston and bleed screw went back in with a good coat of silicone grease, and not something hygroscopic like brake fluid or some of the other brake lubes. A rebuild kit is cheap, not that much work, and if done in time, little risk of having to buy a piston.
Pitting in the bore is no problem, since nothing seals to it.
No mention of compressibility.
When I get to an intersection, I would much rather the guy coming the other way has new rubber parts, than new fluid.
Too bad they gave no indication of how long it takes the copper levels to become destructively high. You lose a lot of brake fluid on every rebuild/replace. I still suspect if you are changing the rubber parts before trouble occurs, the brake fluid will be gone before it goes bad. The more I think about this, the more I think it is better to rebuild in a timely manner, than replace. That way I know the piston and bleed screw went back in with a good coat of silicone grease, and not something hygroscopic like brake fluid or some of the other brake lubes. A rebuild kit is cheap, not that much work, and if done in time, little risk of having to buy a piston.
Pitting in the bore is no problem, since nothing seals to it.
No mention of compressibility.
When I get to an intersection, I would much rather the guy coming the other way has new rubber parts, than new fluid.
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Nice to see how the issue keeps being skewed. Not sure where anybody ever claimed that brake components will last indfinitely due to the fluid being changed. Not sure where anybody said brake components need not be serviced as needed. I suppose I can't read well, or lack comprehension. I'm also not sure why I wouldn't want fresh brake fluid every two years to maintain brake performance. A lowererd boiling point of brake fluid due to moisture maybe acceptable to some, to me it's gross negligence. Just call me thickheaded.
I think they purposely avoided giving a specific time interval in that study report because it probably varies all over the place. If all you have to do is dunk a test strip in the reservoir, who wouldn't choose to do that and change the fluid when it's really needed, rather that blindly follow a time interval. I wonder where you can get these test strips.
Edit: I answered my own question by doing a Yahoo search for "brake fluid test strips".
I definitely agree with labman that doing a regular caliper rebuild would probably make the brake fluid issue moot. It's really the best insurance against brake failure, but lots of people get away with never doing this and have no problems either. This includes lots of people in salt-happy Michigan. I still think there's something we're missing that would tell us why some people have a lot of trouble with brake system corrosion and others don't (if some cars are experiencing corrosion and others aren't), or why the corrosion affects some and not others (if the corrosion happens in every car).
[ June 09, 2004, 09:27 AM: Message edited by: Matt_S ]
Edit: I answered my own question by doing a Yahoo search for "brake fluid test strips".
I definitely agree with labman that doing a regular caliper rebuild would probably make the brake fluid issue moot. It's really the best insurance against brake failure, but lots of people get away with never doing this and have no problems either. This includes lots of people in salt-happy Michigan. I still think there's something we're missing that would tell us why some people have a lot of trouble with brake system corrosion and others don't (if some cars are experiencing corrosion and others aren't), or why the corrosion affects some and not others (if the corrosion happens in every car).
[ June 09, 2004, 09:27 AM: Message edited by: Matt_S ]
I'm in Colorado and perhaps our very dry climate helps somewhat.
I checked my two Honda owners manuels which said every three years or 45 thousand miles.
I'll follow you guys advise and start changing mine. I figure now that I know about it it will bite me too if I don't..........
What I don't get (perhaps I am a moron) is why testing at the reservoir would give you an indication of the overall condition of the fluid. Wouldn't the fluid at the wheels be much more deteriorated? Otherwise, why bother opening bleed screws? You could just change the fluid in the reservoir a few times and it would percolate down.
I would think if you want to get an idea of the condition of the fluid you would have to open up each of the bleeders and test it there.
According to the article the real damage to the fluid occurs in the lines. Since fluid regularly returns from the lines to the reservoir, copper contaminated fluid should show up in the reservoir. It should also show up in the calipers, but the reservoir is easier to check.
The article says dark fluid may still work fine. It also says enough moisture to cause problems seldom happens. Both of these points are very consistent with my experience and the recommendations of the American manufactures. Loss of braking due to boiling seldom happens. Usually they fade completely long before that happens.
So how does this nasty, copper contaminated fluid corrode caliper pistons between the seals and the boots where it does not wet them? How does changing it protect parts it doesn't touch?
The article says dark fluid may still work fine. It also says enough moisture to cause problems seldom happens. Both of these points are very consistent with my experience and the recommendations of the American manufactures. Loss of braking due to boiling seldom happens. Usually they fade completely long before that happens.
So how does this nasty, copper contaminated fluid corrode caliper pistons between the seals and the boots where it does not wet them? How does changing it protect parts it doesn't touch?
I have a small Auto repair shop in the family. We
use the Motive Bleeder and recommend a once a year brake fluid change with the annual state inspection. We pull four wheels and have it on the lift anyway. You do not have to worry about snaping a brake bleeder screw if they are exercised annually with the brake bleeding. We have specials where we package a few items with the State inspection and Brake Bleeding is one of the most well received. Some customers stop back and say hey what did you do to my brakes, their working great now.
use the Motive Bleeder and recommend a once a year brake fluid change with the annual state inspection. We pull four wheels and have it on the lift anyway. You do not have to worry about snaping a brake bleeder screw if they are exercised annually with the brake bleeding. We have specials where we package a few items with the State inspection and Brake Bleeding is one of the most well received. Some customers stop back and say hey what did you do to my brakes, their working great now.
I just did my girlfriends '97 Taurus last night. The fluid came out a dark brown. I can't understand how anyone would change the stuff all of the time.
I'd much rather he have both, but since one is an easy job and one need not be done the part has deteriorated, I'd like to know he had his fluid changed regularly.
I had a '93 Ciera. My mother got in a wreck do to ineffective brakes. When I bled them, no bubbles came out, only old dark murky fluid. The pedal feel improved enough to be able to lock up the brakes on dry pavement, where they had not been able to before.
I simply cannot understand why anyone would leave old fluid in their system. It absorbs water and salt, and this has been proven. It is also proven that this degrades the performance of the fluid. These facts alone are more than enough reason to change it regularly.
Proven? Not according to the study already referenced here. It seems you fluid changing fanatics ignored it. It claims there is very little problems with color or water absorption. http://www.babcox.com/editorial/bf/bf50412.htm
I am still waiting for an explanation of how changing the fluid protects the parts of the brake system most subject to failure that are not in contact with it.
I am still waiting for an explanation of how changing the fluid protects the parts of the brake system most subject to failure that are not in contact with it.
Those would be the parts generosly coated with your Red Herring oil.
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