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Differences in Hydraulic Fluid.

CT18fireman

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Anyone have a source to spec different fluids. I guess I am mainly thinking about compression strength differences if there are any.

For example, previously I have run a Fisher Snowplow (originally used ATF) on a Central Hydraulic equipped truck. I saw no difference in performance. What I am wondering though is say one type of fluid able to handle a greater load in the same cylinder?

Say you have a dump truck will one fluid allow you to lift more? Or in a backhoe does one fluid allow for more breakout?

Obviously the differences are probably slim. I also realizze that all manufacturers want you to use their fluid for best performance etc.

I know that temperature has a pretty big affect on performance usually. Are there certain temps where fluid is at its optimum, what ranges really start to affect performance.

Probably thinking a lot more then I need to but as I have a complete fluid change coming on my TLB and the Dump I thought I would try to optimize the equipment as best as I can.
 

Ross

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Cannot Compress Hydraulic oil. Doesn't matter how much pressure you apply to it. Cannot fit 100 ml 3 of oil into a 99 ml 3 Container.

This is venturing into the realm of Fluid Mechanics. Viscosity = x = 1E/2 e 3 :confused: And all that.

What I am wondering though is say one type of fluid able to handle a greater load in the same cylinder?

And the answer is ... No ...

Using thinner oil would probably blow the seals out quicker thou.
Brake fluid DOT 5. Wouldn't even reach the celing pressure. Just blow past everything.

ATF and HYD oil have similar Viscosity's. The difference would be too slight to notice BUT, The pump (depending on what Type/Make) would have to work a little harder to reach Full pressure = Slightly Less component life. This is true across the whole system.

Ross
 

CT18fireman

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OK that is what I was thinking. That the fluid differences are insignificant in load applications etc.

Pumps and I guess motors would be where fluid differences would be more apparent.
 

Ross

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OK that is what I was thinking. That the fluid differences are insignificant in load applications etc.

Pumps and I guess motors would be where fluid differences would be more apparent.

That's another Question thrown in there.

Well any oil could be used in a Hydraulic System.

Manufactures sort of design a system around the oil. You could use Beer to operate a system if the components were designed to withstand and cope with the requirements for that particular fluid at Full Push.

Scientists and engineers have decided that Hydraulic oil is the best mix of viscosity, Heat and durability requirements. Manufactures can now take the DATA/Numbers for this fluid and Use it to design systems that perform to there best.

An example. O&K Use none standard Hydraulic oil. They changed the oil, there by changing the numbers in the equations to match there system better.

Piston Pumps don't like different fluids. There whole Lube, Flow and Pressure parameters are designed around oil flow.

Ross
 

Ford LT-9000

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Hydraulic oil is more of a mineral oil based where as ATF is more for transmission use and absorbing heat.

For hydraulics you should use hydraulic fluid and the correct weight of oil. Some machines use a 10 weight engine oil which is mainly old Cat machines.

On a old dump truck I have been running the hoist leaks so bad we are using used canola oil that is stained through a strainer. It works the hoist goes up just as good with it even better actually than AW46 hydraulic oil its also more enviromentally friendly and cheap.
 

thejdman04

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Different oils are differnt viscosity's resist thermal break down etc etc, sue whats called for. I dont mean necessarily thier branded oil but hydraulic oil wher eit shoudl be and atf where its called for
 

CT18fireman

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Just for the record I wasn't thinking of running atf, only saying that I had put hydro fluid into a plow that had been made for atf and the plow is still working fine in terms of the cylinders.

I am thinking mostly of the cylinders. I plan on using recommended fluid, only was thinking of any performance gains or draws.
 

surfer-joe

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ATF and HO are really designed for two quite different applications, yet many of their characteristics are close to being the same. As someone else mentioned, the ATF is specced more for gear and clutch pack lubrication and protection, whilst HO is more designed for work in close tolerance pumps, valves and cylinders. (hydraulic systems)

ATF (or C2/3/4) will work well in many HO applications, but not vice versa for very long. You likely would not notice any short-term performance differential either way, but eventually an HO in a drivetrain application (other than hydrastatic) will significantly shorten it's life. Manufacturers generally spec system components (seals, o-rings, etc.) for one particular type fluid to optimize performance and longevity.

Both fluids have pretty comparable temperature specs, here again you would not notice much performance differential. If you were working in really hot or cold climates, you might want to consider working with an HO that is specced for that situation.

If you have an especial component situation, you will likely want to follow the manufacturers recommendations.

Good luck
 

Orchard Ex

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You could use Beer to operate a system if the components were designed to withstand .......

I'd like to know more about changing my systems over to run on beer... :beerchug
Would a Porter or Stout be better because of viscosity, or a would a lager dissipate heat better? How do I keep the help from putting a tap on the hydraulic tank?..... :drinkup
I have 5 gals of hydraulic fluid fermenting in the basement.:thumbsup
 

CAT793

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Cannot Compress Hydraulic oil. Doesn't matter how much pressure you apply to it. Cannot fit 100 ml 3 of oil into a 99 ml 3 Container.
Ross

You can indeed compress Hydraulic Oil. It compresses at a rate of 1/2 a percent of volume at a pressure of 1000 psi. This is one of the causes of Hydraulic Shear in modern Hydraulic oil.

You can compress any liquid. That is why there is pressure at the bottom of the ocean.
 

Garrie Denny

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A question please Ross; I have just put 10w-40 oil in my old Fiat Dozer(70ci) ad apparently it is not the correct one it has run approx 12 hours with this oil, would this oil when drainwd be ok to use in my hydraulics for ram blades, as the operating lever main o ring seal leaks out oil and i am forever topping this up, thanks Garrie.
 

greggn

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A question please Ross; I have just put 10w-40 oil in my old Fiat Dozer(70ci) ad apparently it is not the correct one it has run approx 12 hours with this oil, would this oil when drainwd be ok to use in my hydraulics for ram blades, as the operating lever main o ring seal leaks out oil and i am forever topping this up, thanks Garrie.
The engine oil will have probably picked up a bit of carbon etc. I wouldn't do it.
 

Garrie Denny

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Your reply picked up carbon, im ignorant to what that means and the possible down-side if I used that oil,taking into consideration i use 15/30 oil in the hyd side now, thanks Garrie
 

joispoi

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Carbon is the soot from combustion that turns the oil black in your engine. I'd mix it with diesel and burn it as fuel before I put it in the hydraulic system. The carbon particles are slightly abrasive. On a side note, how many liters of hydraulic fluid do you add before a new o-ring starts to look cheap?
 

Garrie Denny

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Thanks for the reply,i think ill go your way on the engine oil,as for the o-ring theres only so many days in a month ad i only get to play dozer man on my toy for about 2 per month if im lucky ill get to it when ive got more time up my sleeve.
 
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