# Hydraulic fluid in fisher plows



## LJM5700

Is there a difference of using ATF fluid in a fisher plow? I was told by the dealer that it is recommened and I was curious why?
I was told that I needed to use Fisher Hydraulic fluid only.


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## peteo1

Your Fisher dealer told you this???? I used Fisher for years and everything I've ever heard has been use only Fisher fluid. Atf doesn't work well in cold temps from what I understand.


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## LJM5700

*Hydraulic fluid*

Thanks for the tip.
I wasn't sure if it would harm the pump.


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## Morrissey snow removal

atf works fine thats all we use have used it for yrs never had a problem


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## goel

Same here. I just add a splash of alcohol to it to prevent freezing.


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## 2COR517

ATF is fine for an egine driven system. All others should have Fisher blue only


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## leolkfrm

when the function on the plow makes the money...why do so maney want to save 2-3 dolars?...just wondering..bwai


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## potskie

My dealer doesn't even have the Fisher blue stuff in stock. They sell their own mix at a massively lower price. It's essentially just bulk and repackaged ATF .


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## JCByrd24

I highly doubt a fisher dealer is repackaging bulk ATF for use on electric pumps in Canada. More likely it is bulk aircraft hydraulic fluid, which is what plow fluid is. The performance of atf below 15 or so degrees F is noticeably worse, as it is much thicker. Your speed will be slower and your pump will draw more amps, so your headlights will dim more, etc. I converted a couple years ago and I was impressed with the difference right away. I'm still on my first gallon of fluid as well.


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## ducaticorse

ATF is fine, but you should be purging your entire system of the blue before you use it. I use ATF in all my plows and it works fine. Just don't mix the two.


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## theplowmeister

I used to use ATF for years, never had a problem. I now use the blue stuff. I like it better in the cold cold, also if you use ATF the red spot in the snow... is it from your trany or the plow?.... If its blue I know, If its red I know.


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## CAT 245ME

I use Boss fluid in my Fisher. No issues.


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## OC&D

I've used both over the years, had trucks where the two got mixed, and never had an issue.

I usually use aircraft hydro fluid, but in a pinch I'll use ATF. Should I drain everything after and re-fill with fresh hydro fluid? Yes. Have I ever? No. Would I suggest it to someone else? Yes.


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## jasonv

Depending on the pump, and sometimes the temperatures, ATF is known to FROTH.... badly. Some pumps are fine with it, on others, it will blow out the seals.

What happens is that with the thicker fluids, when an air bubble gets mixed into the fluid, it won't bubble to the surface very fast, so rather than rising up, it will get sucked back down into the pump and churned in to the fluid, becoming froth. As you work it back and forth, up and down, a few times, more air bubbles work into the fluid and get frothed in by the pump. Then you end up with this mass of froth, which takes up more space than straight fluid, so your total froth volume exceeds the reservoir capacity and needs to push out somewhere. Its cold and thick though, so doesn't spill out the small vent, rather blows out the lift cylinder seal.

One of the places where air can get sucked into the system is from the pump inlet at the bottom of the reservoir. When the lift cylinder is fully extended and the fluid is low in the reservoir, that cold fluid may not spill down to the low spot very well, instead, a bit of air gets sucked in directly with the fluid.


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## theplowmeister

CAT 245ME;1559390 said:


> I use Boss fluid in my Fisher. No issues.


Ha I use fisher fluid in my Boss... no issues


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