ATF after sitting in garage

Trav

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So are you implying that ANY fluid container should be discarded that's been left open for any extended period of time?
How can you be certain these effects would be similar in other containers from other manufacturers?
I would say if it is ATF or brake fluid then quite possibly, if this were engine oil I wouldn't be too concerned. I posted this just to show the VOA not to debate using it or trying to get the moisture out, it is already gone with the other used oils for a waste oil furnace a guy takes when I have about 50 gal.
Frankly I am a little surprised at the posters who would actually take the risk and try to use this in a properly working transmission, I learned many years ago clutch plates and water do not mix and are very easily toasted by it.
 
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Trav

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I tossed it, I have plenty of trans fluid in partial qt bottles. That was something I just wanted out of my sight. LOL
 
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Decades ago GM had a patent on a sealed transmission design with a "bladder" to accomodate air expansion. This was primarily to reduce oxygen availability that caused oxidation of the fluid over time. (This was the time period after the whale oil was outlawed and before "synthetic" base fluids were economical and in wide usage. ) But other than this concept (which never made it to production), I'm not aware of "sealed" transmissions. So humidity is going to get in there to an extent, and depending on the operating temps, get burned off too.
 

Trav

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Decades ago GM had a patent on a sealed transmission design with a "bladder" to accomodate air expansion. This was primarily to reduce oxygen availability that caused oxidation of the fluid over time. (This was the time period after the whale oil was outlawed and before "synthetic" base fluids were economical and in wide usage. ) But other than this concept (which never made it to production), I'm not aware of "sealed" transmissions. So humidity is going to get in there to an extent, and depending on the operating temps, get burned off too.
In the report they said this under comments. I hate to think they could bugger a test so badly. They seem to be treating this as a UOA not a VOA even though I told them it was unused just sitting.

Light concentration of water present. All other wear
levels appear satisfactory for first sample. Silicon level
(dirt/sealant material) satisfactory. Unable to obtain
accurate viscosity result at 100C due to presence of
water in sample
. Action: Check for source of water
entry. Resample at next recommended interval to
monitor and establish wear trend.
 
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If I have an extra 'unopened' quart of Brake Fluid in my basement,
I keep it in a plastic bag with a rechargable desicant.
Opened containers are kept for one Week, then disposed of.

I never considered water in Transmission Fluid.
Good info to remember.

I'm curious what some 'used' Trans Fluid analysis is showing any water ?
Will have to do a search some time.
 
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Like others have mentioned, I have to wonder about moisture in ATF while in use. A transmission is not sealed nearly as well as that jug was, and the ATF in the transmission doesn’t absorb enough water to damage anything...
 

MolaKule

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If I have an extra 'unopened' quart of Brake Fluid in my basement,
I keep it in a plastic bag with a rechargable desicant.
Opened containers are kept for one Week, then disposed of.

I never considered water in Transmission Fluid.
Good info to remember.

I'm curious what some 'used' Trans Fluid analysis is showing any water ?
Will have to do a search some time.
Brake fluid is very hygroscopic and needs to changed every two years, ATF very much less so.

ATF fluid has chemistry to deal with moisture.
 
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I think you are correct. No way am I using fluid with any water in it in a transmission. The clutch plates don't handle water well even in small amounts.
I'm with you buddy. That ATF would either be used to flush out a PS system then filled with fresh fluid, a$$uming that fluid could be used in a PS system I was flushing, or get used along with bar oil in my chain saw. Expensive bar oil you bet! But adding any ATF with known water content in it IMO is a very bad idea! I'd rather not gamble with a good AT, especially knowing how harmful water is to them. Smart move getting a VOA before blindly using it.
 
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