I exchanged the brake fluid in our '05 MDX this weekend. I put about 1.6 bottles of brake fluid through it. I have another unopened bottle, and just less than half of one opened one. Can I keep that opened bottle around for a reasonable period of time (6 months) until I do the fluid in our Honda? I have screwed the cap tight, so any moisture would be what's already in it.
Shelf life of open brake fluid
- Thread starter Hokiefyd
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I've never been a fan of any open bottles of any "maintenance" item, and brake fluid especially...I personally wouldn't use it or save it...just too much risk, especially if you "share" a house/garage with ANYONE...especially nosy kids/wives/girlfriends! lol...wouldn't want them "snopping around" and contaminating the fluid.
But perhaps I'm just a little too paranoid
But perhaps I'm just a little too paranoid
I'd buy six weeks, but not since months.
It is hydroscopic. Or is that hygroscopic?
Whatever it is, the water from the air will get in and contaminate it. Not worth the price or risk.
It is hydroscopic. Or is that hygroscopic?
Whatever it is, the water from the air will get in and contaminate it. Not worth the price or risk.
My last open bottle I put in a zip-lock bag with the air squeezed out and stored it inside the house to minimize moisture/dampness exposure.
I buy small bottles. I can buy from dollar general a block away. If I have to I can walk.
An extra six months in the car, where it's even more exposed to oxygen wouldn't be a problem... but somehow in the bottle it would? I don't get it.
Then again, I probably wouldn't use it. Realistically my brakes only get bled about every 5 years. Somehow 6 extra months matters? It makes no sense, but I would use all new (or at least have).
Then again, I probably wouldn't use it. Realistically my brakes only get bled about every 5 years. Somehow 6 extra months matters? It makes no sense, but I would use all new (or at least have).
I had no problem using opened bottle brake fluid in a zip-lock, a year or two after it was opened.
Originally Posted By: ProfPS
My last open bottle I put in a zip-lock bag with the air squeezed out and stored it inside the house to minimize moisture/dampness exposure.
If one had to use an open container, THIS ^^^ is how I would store it, with the addition of putting a large bag/packet of some sort of desiccant into the bag as well.
My last open bottle I put in a zip-lock bag with the air squeezed out and stored it inside the house to minimize moisture/dampness exposure.
If one had to use an open container, THIS ^^^ is how I would store it, with the addition of putting a large bag/packet of some sort of desiccant into the bag as well.
Kestas
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Originally Posted By: crinkles
I did a bit of research this weekend without keeping track of my sources, and read a recommendation of discard immediately and one of up to 3 months, if opened.
As bepperp alluded, that seems rather over the top, considering the fluid is more "open" (less hermetically sealed) at the master cylinder, and THAT fluid is good for two years.
I did a bit of research this weekend without keeping track of my sources, and read a recommendation of discard immediately and one of up to 3 months, if opened.
As bepperp alluded, that seems rather over the top, considering the fluid is more "open" (less hermetically sealed) at the master cylinder, and THAT fluid is good for two years.
I'd say two years if stored properly, regardless of opened or 'unopened' from the store. Stored properly being the key.
The rest is overkill.
The rest is overkill.
Given that brake fluid absorbs moisture, I think its best to always use sealed containers. Maybe keep the opened stuff for situations where something is leaking bad and you need to add some brake fluid before you can get a chance fix it. I have come across situations like that.
The sealed containers are sealed with foil, and full, and unsure what the tiny leftover space was filled with when manufactured. it could have been normal air, dried air or some inert gas.
Sure the fluid in the master cylinder can be considered "open" just like your opened container of brake fluid. But people flush the brake fluid for that very reason, because it was in an open environment and probably absorbed some water.
I think unopened is many years (assuming a foil seal). I would write the date on any brake fluid I stored.
I have 2 open containers now. Unsure how long they have been around or the last time I added brake fluid to one of my vehicles.
The sealed containers are sealed with foil, and full, and unsure what the tiny leftover space was filled with when manufactured. it could have been normal air, dried air or some inert gas.
Sure the fluid in the master cylinder can be considered "open" just like your opened container of brake fluid. But people flush the brake fluid for that very reason, because it was in an open environment and probably absorbed some water.
I think unopened is many years (assuming a foil seal). I would write the date on any brake fluid I stored.
I have 2 open containers now. Unsure how long they have been around or the last time I added brake fluid to one of my vehicles.
Just don't buy the half gallons.
We get a case of the little 1/2 pint bottles and then just discard the unused portion after a year.
As far as moisture simply store them indoors. I kind of like the baggy idea above, too.
We get a case of the little 1/2 pint bottles and then just discard the unused portion after a year.
As far as moisture simply store them indoors. I kind of like the baggy idea above, too.
The open bottle had less than I thought upon further inspection. So I just returned the last unopened one I had and discarded the rest of this opened bottle. In the future, I will probably just flush the rest of the open bottle through whatever wheel is last on the rotation...might as well I guess, rather than throwing the rest away. Next time I do it, I'll have done the second vehicle, so I won't be doing it for at least 2-3 more years anyway.
Thanks to all for your input.
Thanks to all for your input.
Originally Posted By: Donald
The sealed containers are sealed with foil, and full, and unsure what the tiny leftover space was filled with when manufactured. it could have been normal air, dried air or some inert gas.
Motul's RBF products are filled with nitrogen gas in that 'leftover space', and then sealed, or so they claim.
The sealed containers are sealed with foil, and full, and unsure what the tiny leftover space was filled with when manufactured. it could have been normal air, dried air or some inert gas.
Motul's RBF products are filled with nitrogen gas in that 'leftover space', and then sealed, or so they claim.
I used to save it but no longer do. Periodically I suck the master cylinder down and replace it. Overkill..yea.
I to had always heard that an open container would be quickly contaminated if not used up quickly. I recently had a chance to test that theory i had a 3/4 full 250 ml container of Prestone DOT 4 Brake Fluid sealed tight and stored in climate controlled workshop for about 11 months, bought a new battery fluid moisture tester tested fluid showed zero contamination.
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