What's the rationale for changing brake fluid?

[skipsor]

Before you answer, be aware that I have made an appointment to have mine changed in 10 days before we start on a two month, cross country trip.

Before owning a MH I never heard of changing the brake fluid. I used to race Corvettes and we did some horrific braking and, to the best of my knowledge, no one ever changed the fluid. Or maybe there was too much beer in my system and I didn't get the word.

From what I understand, water gets into the lines and when the brakes are used to the point of getting very hot, the water boils, turns to steam and you have no brakes.

This leads me to three questions.

1. How does the water get into a closed system in the first place?

2. Is this a problem that is more prevalent in high humidity areas, i.e., the southeastern states as opposed to the southwest where I live?

3. Have I just been lucky all of these years? If so, I'd rather be lucky than good any time.

[skipsor]

Before you answer, be aware that I have made an appointment to have mine changed in 10 days before we start on a two month, cross country trip.

Before owning a MH I never heard of changing the brake fluid. I used to race Corvettes and we did some horrific braking and, to the best of my knowledge, no one ever changed the fluid. Or maybe there was too much beer in my system and I didn't get the word.

From what I understand, water gets into the lines and when the brakes are used to the point of getting very hot, the water boils, turns to steam and you have no brakes.

This leads me to three questions.

1. How does the water get into a closed system in the first place?

2. Is this a problem that is more prevalent in high humidity areas, i.e., the southeastern states as opposed to the southwest where I live?

3. Have I just been lucky all of these years? If so, I'd rather be lucky than good any time.

[Paul Heuvelhorst]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by skipsor:
...Before owning a MH I never heard of changing the brake fluid... From what I understand, water gets into the lines and when the brakes are used to the point of getting very hot, the water boils, turns to steam and you have no brakes. </div></BLOCKQUOTE>
I've never heard the "water" suggestion before. Changing brake fluid is a maintenance item, just as changing motor oil and transmission fluid. Brake fluid can "boil and burn" through the hard use over excessive miles, just a transmission fluid can, and lose it's effectiveness.

If you check the owner's manual you'll find there are suggested mileage intervals for all these items.

Most brake shops will recommend you flush and change the brake fluid when you replace brake linings, which puts this interval at +/- 50,000 miles.

[DriVer]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Paul Heuvelhorst:
I've never heard the "water" suggestion before. </div></BLOCKQUOTE>Paul, Brake fluid does absorb moisture; it's like oxygen and carbon monoxide. You can research this but that's just the facts as I know them. Brake fluid does not wear out BTW.

I changed my fluid at some 58,000 miles and I still have all my original brake parts.

[dieselclacker]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by DriVer:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Paul Heuvelhorst:
I've never heard the "water" suggestion before. </div></BLOCKQUOTE>Paul, Brake fluid does absorb moisture; it's like oxygen and carbon monoxide. You can research this but that's just the facts as I know them. Brake fluid does not wear out BTW.

I changed my fluid at some 58,000 miles and I still have all my original brake parts. </div></BLOCKQUOTE>

Also water can accumulate in the brake hydraulic system by condensation, caused by wide temperature changes over a long period of time. Heavy or improper use of brakes can cause fluid to actually boil, which will cause moisture, and air bubbles to form in the system. Personally I like DriVer have never been particularly hard on brake, and have not yet changed the fluid in my motorhome. I think some owners suffer from a little overkill on some maintenance items.

Just my thoughts on the subject

Dieselclacker

[Paul Heuvelhorst]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by DriVer:
Paul, Brake fluid does absorb moisture; it's like oxygen and carbon monoxide. You can research this but that's just the facts as I know them. Brake fluid does not wear out BTW. </div></BLOCKQUOTE>
Thanks for the information... if you try, you learn something new every day. I stand corrected.

The point I was trying to make, even tho' wrong about the water, is that brake fluid can become contaminated and should be replaced.

Thanks for your explanations.

[MikeT]

From page 73 of the Workhorse Chassis guide ---



BRAKE FLUID CHANGE
Although there is not a recommend service interval to change the brake fluid listed in your
Owner's Manual, the recommendation by a number of the brake manufacturers is every two to
three years. If the fluid becomes contaminated, change immediately. Use Delco Supreme No.
11 Hydraulic Brake Fluid (Dot No. 3) or equivalent.
New brake fluid is clear with a brown-orange tint. Brake fluid absorbs water and prevents it
from settling in lines causing damage. As water is absorbed, the fluid will darken to the point
that it appears to be almost black. This would be a good time to change the fluid.