Can I mix ATF fluid?

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Joined
Oct 15, 2016
Messages
679
Location
USA
Vessel Name
Speedy Charlotte
Vessel Make
Beneteau Swift Trawler 44
Hi everyone, I'm about to take an 8 hour trip back to San Francisco from Monterey and it looks like one transmission could use a little extra fluid.

The engines were recently serviced but I'm not sure of the brand they put in. Volvo specifies an ATF fluid that is Dexron II or III compliant. So whatever they put in, I assume it was Dexron II or III compliant.

I have Western Family brand on the boat that I had purchased a while ago when I brought the boat down to Seattle after purchase. But at that time we had no idea if it was the correct type or not. We just bought it in case of an emergency and it was the only one we found in the area. Point is, the Western Family brand probably isn't what the Volvo mechanic put in.

That said, it does say it is Dexron II and III compliant.

Is there any issue using the Western Family brand even though it may not be the brand in the transmission now? Or as long as it is Dexron II or III compliant am I okay?

Thanks!!!!
Mike

P.S. I texted the mechanic but it's late so no idea if I'll get a reply.
 
No worries as long as same type AS Dexron 11/111, it probably all comes from the same manufacturer in the be ginning before it's branded any way,Very commonly done

Cheers Steve ( NZ Chief Eng 1)
 
According to Dexron, new Dexron VI / Dexron VI Approved is reverse compatible with all older Dexron ATF types.
 
No worries as long as same type AS Dexron 11/111, it probably all comes from the same manufacturer in the be ginning before it's branded any way,Very commonly done

Cheers Steve ( NZ Chief Eng 1)



Thanks Steve and Archie. Looks like this is specifically II and III compatible. Here is the label. IMG_9346.JPG
 
I have Western Family brand on the boat that I had purchased a while ago when I brought the boat down to Seattle after purchase.

How old is it and has it been opened? If you're not planning on changing the fluid anytime soon, I would opt for a new container of fluid if this one is old or opened. It's cheap insurance.

Ted
 
How old is it and has it been opened? If you're not planning on changing the fluid anytime soon, I would opt for a new container of fluid if this one is old or opened. It's cheap insurance.



Ted



It's 8 months old, unopened.
 
Why does it mater if atf has been opened? I have seen this before but interested in the why.
Thanks
 
I can't answer the question, but suspect it has to do with impurities or moisture in the form of humidity entering the open container. Brake fluid is another one that you're not supposed to use after a long storage period from first opening the container.

Ted
 
brake fluid will definitely suck in moisture, Ive never seen tranny fluid do it.

Bugs will sink to the bottom though.
 
I can't answer the question, but suspect it has to do with impurities or moisture in the form of humidity entering the open container. Brake fluid is another one that you're not supposed to use after a long storage period from first opening the container.

Ted

Brake fluid is hyrdoscopic, that is, it has an inherent ability to absorb water. ATF, I think not.
 
From Wikipedia...
"Dexron-II was introduced in 1972 with alternative friction modifiers such as Jojoba oil. However, it caused problems with corrosion-prone solder in GM's transmission fluid coolers;[2] accordingly, corrosion inhibitors were added to the product. The resultant fluid, released in 1975, was called Dexron-IID. However, the corrosion inhibitor made the new fluid hygroscopic, which while it was not a major problem in automatic transmissions, made Dexron IID unsuitable for other hydraulic systems in which it was commonly used.[2] A further reformulation, to address excessive hygroscopicity[citation needed], but primarily to improve low temperature performance (20,000cP @ -40C vs 50,000cP@-40C for Dexron-IID) was named Dexron-IIE (GM Spec GM6137M)."

https://en.wikipedia.org/wiki/DEXRON
 
Brake fluid is hyrdoscopic, that is, it has an inherent ability to absorb water. ATF, I think not.

I never bothered to investigate why using old opened bottles was discouraged. The stuff is too inexpensive to waste the effort.

Ted
 
As long as sealed in original container nothing wrong to keep oils for lengthy periods it depends a little as follows,Petroleum products “go bad” because of chemical reactions that are started when they get exposed to things like air and oxygen, heat, light and water.

1)If the motor oil contains elements like copper and iron, that could contribute to its lower shelf life since these elements act as catalysts and speed up oxidation.
2)Extreme temperatures such as below 0ºF or above 100ºF can affect the stability and the ability of the motor oil to effectively lubricate the engine. Very low temperatures can result in the formation of sediments in the motor oil.
3)If you see that the additives seem to have separated from the oil, it is not safe to use. You must also check its color. Usable motor oils have a clear appearance and if you notice any milkiness or haziness, that is a sign of water contamination. A change in the original color of the motor oil could also indicate its instability.

With all that said most manufacturers agree that 5 years is the maximum shelf life in perfect conditions (THIS DOES NOT APPLY TO BRAKE FLUID)


Cheers Steve (MIIMS-Lloyd's Maritime)
 

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