Un-opened brake fluid have a shelf life?

[steven88]

Just curious to know if UN-OPENED Brake Fluid has a shelf life? I was able to score some expensive brake fluid for free...but I don't have any use for it until a year or two later...

so whats the deal with UN-OPENED brake fluid? I heard about stories with OPENED brake fluid...being okay to use again, as long as it's sealed...but cannot withstand long term shelf life

 

[Rickey]

I don't actually know what the shelf life is. Considering that opened fluid in a vehicle is commonly used for years and years:unopened fluid in a well sealed container should have at least 10 years or more shelf life. And thats just a wild guess on my part. Brake fluid has an affinity for water and will happily absorb same from the environment after the container has been opened. This lowers the boiling point which is bad in a brake hydraulic system at the high temperatures reached in the vicinity of the friction surfaces. I have used fluid that was in a tightly resealed container 2 or more years after it's first opening. No bad results were obtained. Good luck. Rickey

 

[steven88]

Rickey - thanks! thats good to know sealed brake fluid can last awhile...

anybody else have inputs?

 

[Tones]

I don't know either, but I think if it is in a can there is a better chance that it will be fine than if it is in plastic. The plastic containers are more permeable.

 

[steven88]

Tones - its actually plastic

 

[benjamming]

Just for curiosity: What brand fluid is it?

 

[steven88]

motul rbf600...i think its overkill if you buy it for street driving...but hey, scored it for free...hehe

 

[Ray H]

Cans can rust. I'd have to see the proof that plastic is permeable to any degree sufficient that "spoilage" of the product inside resulted. (I've yet to find a properly sealed plastic bottle of brake fluid that was moist with fluid that had permeated to the exterior surface. For that matter, aren't soda-pop bottles plastic? Under pressure? Wish I had a buck for every bottle of soda I've found on store shelves sittting in a sticky goo that resulted from the pop permeating through the bottle wall...

)

 

[Tones]

As I mentioned, I'm not claiming to know it all here.

I recall a similar situation with beer bottles, the beer would oxidize in plastic, which is why it was never bottled in plastic until recently when they developed some kind of liner for the bottles.

 

[wilbilt]

If you are really worried about it, why not overseal it in some ziploc bags until ready for use? If one layer of plastic is OK, three must be better!

As for the beer, drink it immediately, as it has no shelf life...

 

[RinconVTR]

All plastic is technically permeable. Its not that soda bottles will ever leak, we’re talking about such little passable amounts of vapor, it’s near impossible to measure. (and some plastics like nylon, actually absorb moisture)

I design enclosures that must withstand the worst elements the earth can dish out on it own, and unless potted with epoxy, all enclosures must be metal or glass to eliminate any water vapor passing thru. Brake fluid, as we all know, absorbs water. But would it be enough to ruin it over 10 years or so? IDK. But $5 buys you a large container of new stuff. Why chance it? Buy some known fresh fluid if in doubt.

 

[Kestas]

or transfer leftover fluid to a glass or metal container, like an old Valvoline DOT 4 container.

 

[alreadygone]

If it's ok in mastercyl. reserviors when it's 10-15 yrs old, I doubt it'll ever go bad if a sealed container stored inside.
Bob

 

[benjamming]

But many don't think it is ok in a master cylinder reservior for 10-15 years.

 

[alreadygone]

Don't know that it is ok,,,but it still works!

Bob