Brake Fluid Shelf Life

[evil_henchman]

How long do you keep brake fluid in your brake system before you change it? That's how long I'd keep it on the shelf, opened or unopened.

That seems ridiculously conservative to me. Heck, for all you know, it could be sitting on the shelf of the auto parts store or in a distribution warehouse for a year or two before you buy it.

I don't have any hard information on the shelf life of a sealed brake fluid container, but given that there are no expiration dates on the containers, I'd expect it to be a fairly long time - certainly a few years or so. The stuff is designed to be basically inert and non-volatile - that's why it is so tough on the environment when it's dumped.

- Mark

It sits in my brake system for years so maybe not so ridiculous after all eh? Or do you change yours every few months? (To illustrate the opposite ridiculous extreme)

:lol:

 

[Powerman]

Buy small bottles, opened fluid is hygroscopic . Lasts a long time in an unopened container.

I change the fluid yearly in every vehicle I own, never had a caliper or master cylinder problem.

 

[weekend rider]

I wish the facts that are being stated about brake fluid were accurate and and part of the directions on the can. Brake fluid loosing its boiling point because it is opened???????? Where did that come from???? What do the directions say, ask a chemist? Inacturare testing in a non controlled inviroment without guide lines... Never have heard of any person's brakes that have failed because of using brake fluid that is a a year or more old, nor any problems with master cylinder or calipers. where fdo these myths come from????? :blink: I wish the facts that are being stated about brake fluid were accurate and and part of the directions on the can. Brake fluid loosing its boiling point because it is opened???????? Where did that come from???? What do the directions say, ask a chemist? Inacturare testing in a non controlled inviroment without guide lines... Never have heard of any person's brakes that have failed because of using brake fluid that is a a year or more old, nor any problems with master cylinder or calipers. where do these myths come from????? :blink:

 

[FlyingLow]

I wish the facts that are being stated about brake fluid were accurate and and part of the directions on the can. Brake fluid loosing its boiling point because it is opened???????? Where did that come from???? What do the directions say, ask a chemist? Inacturare testing in a non controlled inviroment without guide lines... Never have heard of any person's brakes that have failed because of using brake fluid that is a a year or more old, nor any problems with master cylinder or calipers. where fdo these myths come from????? :blink: I wish the facts that are being stated about brake fluid were accurate and and part of the directions on the can. Brake fluid loosing its boiling point because it is opened???????? Where did that come from???? What do the directions say, ask a chemist? Inacturare testing in a non controlled inviroment without guide lines... Never have heard of any person's brakes that have failed because of using brake fluid that is a a year or more old, nor any problems with master cylinder or calipers. where do these myths come from????? :blink:

Do you mind? Those of us with dyslexia are doing double takes on this one. I am inclined to agree, though.

Do you mind? Those....

 

[mcatrophy]

... Brake fluid losing its boiling point because it is opened???????? ...

It's not the brake fluid that boils, it's the moisture that has been absorbed.

When water does boil, the steam produced is about 600 times the volume of the water from which it came (if memory serves), so a small amount of water becomes a significant proportion of the total volume in your brake system. The real problem is that steam is a gas, and so is compressible, which means you don't get the required pressure on your brake pads as you squeeze the lever.