ATF vs Power Steering Fluid

[jhwis]

Is ATF lighter than your typical power steering fluid? What is the lightest oil you'd use as power steering fluid in an older tractor? Just a general question assuming no other specifics known.

 

[Brian G. NY]

Is ATF lighter than your typical power steering fluid? What is the lightest oil you'd use as power steering fluid in an older tractor? Just a general question assuming no other specifics known.

This is not a definitive answer to your question.
But....though they are not tractors, both my 2005 and 2014 Toyota Tacomas call for DEXRON II or III for the Power Steering.
I would guess that it is probably a bit better than your "run of the mill" P/S fluid you can pick up at Walmart but I would also guess that the viscosity is close to the same.
I have 2 log splitters; one of which is filled with Dexron PS fluid and the other common hydraulic fluid.
Apparently, the PS is of lower viscosity than Hyd. Fluid as it is nearly impossible to start the one with Hyd. fluid in very cold weather like we're having now.
I have "hytran" fluid in the PS on my Allis D-17 and the steering is a "bit stiff" in very cold weather.
"Someday" I intend to change it over to Dexron P.S. fluid.

 

[Rich'sToys]

Probably 30 years ago I put ATF in the power steering of one of my John Deere 50's. That was before I knew that Deere had its own power steering fluid. It's still in there, and working fine.

 

[rustred]

Is ATF lighter than your typical power steering fluid? What is the lightest oil you'd use as power steering fluid in an older tractor? Just a general question assuming no other specifics known.

They are both hyd oils. Atf has additives for the transmissions. Not going to hurt a thing using atf in these old power steering’s. I use it also. At work in the oil patch we Tryed atf oil in the hydraulic top drive units. Talking like 4 barrels of oil. Tryed this due to the -40
Winter’s. We found the pumps were not lasting as long with atf. With the standard hyd oil we used # 68 in summer. Then when winter came had to suck held the oil out and add # 22 oil to thin it. In cold weather the hyd cylinders would barely move. Always best to stick with what the chiefs or manufacturers decide on. As for these old tractors it’s not worth worrying about. As they say pick your poison.

 

[Newgenerationdeere]

Is ATF lighter than your typical power steering fluid? What is the lightest oil you'd use as power steering fluid in an older tractor? Just a general question assuming no other specifics known.

I’ve used 15 40 , 80 90 ,atf And tractor hydraulic oil and on a rare occasion when I couldn’t get anything else power steering fluid

 

[rustred]

I’ve used 15 40 , 80 90 ,atf And tractor hydraulic oil and on a rare occasion when I couldn’t get anything else power steering fluid

I would to before risking burning out the pump in an emergency. As they say any oil is better than no oil.

 

[joeysmith]

I usually run engine oil in ps pumps that are flange mounted an have the possibility of leaking into the engine crankcase

 

[Bob Bancroft]

Is ATF lighter than your typical power steering fluid? What is the lightest oil you'd use as power steering fluid in an older tractor? Just a general question assuming no other specifics known.

I don't know what they're using now, but conventional Gleaners used ATF in the hydraulic systems. Maybe because they were Cessna components, and ATF looked like aviation 5606 hyd. oil? Just a guess.

 

[BarnyardEngineering]

Is ATF lighter than your typical power steering fluid? What is the lightest oil you'd use as power steering fluid in an older tractor? Just a general question assuming no other specifics known.

I think some specifics need to be known here. Specifically, what problem are you trying to rectify?

If the manufacturer calls for power steering fluid, I use power steering fluid. If the manufacturer calls for a specific type of ATF (there are many), I use that specific type of ATF. Except in an emergency when the correct fluid is not available and I need to finish out the day and/or get the machine home; as someone above said, any oil is better than no oil. In either case, if the mechanism that uses the fluid is not working as expected, I diagnose the mechanical problem that is causing it. Playing games with the fluids is not the way to fix the problem.

 

[Mark-Ia]

If it's a John Deere Two-Cylinder, they have their own special oil.

 

[sotxbill]

USED to be.... atf and power steering fluid... started out as a 20wt mineral oil.. then a red dye had to be added ie TYPE A atf fluid was born... Then... a viscosity stiffener was added to the atf, but not necessarily to the power steering fluid.. However the power steering could use the better atf oil. The common viscosity additive was whale oil.. but the ban of 1978 banned uses of whale oil world wide... so the atf changed again, to other viscosity additives, anti oxidation additives. The GM camp used a minor friction additive in their atf where ford type f severly limited the antifriction additves. so now there are two types of atf. PS fluid still did not work for atf, , but you could use the better atf oils in power steering. Due to higher pressures and more heat, atf was upgraded in the 80s again,, and then in the 90s to a paritial synsthectic blends. PS fluids had minor upgrades for heat, but could still use the much much better atf. ATF fluids had to carefully control the amount of anti friction additives to keep the internal clutches and wet brakes from slipping, and this means you could not a modern motor oil in them or you would burn up the clutches. Not a problem in PS systems. SO yes.. for the most part, you can use an ATF in the power steering, but you CAN NOT use a power steering fluid in a ATF. And you can never use a motor oil in a Automatic trans or tractor system with wet pto clutches, muti range clutches, and wet brakes. Today, there are all types of exotic fluids and still the basic fluids, but again, the PS fluids are usually just heat and oxidation resistant, but otherwise a lower grade spec. On tractor power steering systems where the PS pump has a bad front seal, and is leaking fluid into the engine oil system, It common to just put the req engine oil in the PS reservoir, as it will end up in the engine slowly over time. BUT NEVER put engine oil in a trans system with wet clutches or wet brakes or expect the system to slip, and burn up the discs from slipping. Old spanish tradition.

 

[BarnyardEngineering]

Wasn't "Type A" made from whale oil?

 

[Newgenerationdeere]

I would to before risking burning out the pump in an emergency. As they say any oil is better than no oil.

I can’t see getting to particular in a machine out of warranty and it’s a simple open center hydraulic pump

 

[showcrop]

Ford speced hydraulic for my 9000.

 

[Hobo,NC]

I used ATF then I started keeping UTF Ford/New Holland M2C134A/B/C/D spec in stock I use Ford spec on most everything. If you buy a bottle of power steering fluid at a parts store I would wager its a UTF are a hydraulic fluid that has a viscosity thicker then ATF.

Several times in the last 52 years I ran across where it made a difference the difference was the system had a whine on cold start up. The noise could be a restriction in a hose are a filter screen in the reservoir restricted. Only one time I saw the fluid make a difference it was on a 80's Toyota its been so long I don't remember if it was the fluid are a hose issue. I remember it was not the pump are steering gear so that leaves fluid are hoses. That may have been when I started using UTF in P.S. systems are why I stopped using ATF unless it specked ATF.

I have brought new P.S. pumps from a dealer and asked for OEM fluid they gave me a bottle of generic P.S. fluid that can be brought at any parts store.

 

[Fritz Maurer]

USED to be.... atf and power steering fluid... started out as a 20wt mineral oil.. then a red dye had to be added ie TYPE A atf fluid was born... Then... a viscosity stiffener was added to the atf, but not necessarily to the power steering fluid.. However the power steering could use the better atf oil. The common viscosity additive was whale oil.. but the ban of 1978 banned uses of whale oil world wide... so the atf changed again, to other viscosity additives, anti oxidation additives. The GM camp used a minor friction additive in their atf where ford type f severly limited the antifriction additves. so now there are two types of atf. PS fluid still did not work for atf, , but you could use the better atf oils in power steering. Due to higher pressures and more heat, atf was upgraded in the 80s again,, and then in the 90s to a paritial synsthectic blends. PS fluids had minor upgrades for heat, but could still use the much much better atf. ATF fluids had to carefully control the amount of anti friction additives to keep the internal clutches and wet brakes from slipping, and this means you could not a modern motor oil in them or you would burn up the clutches. Not a problem in PS systems. SO yes.. for the most part, you can use an ATF in the power steering, but you CAN NOT use a power steering fluid in a ATF. And you can never use a motor oil in a Automatic trans or tractor system with wet pto clutches, muti range clutches, and wet brakes. Today, there are all types of exotic fluids and still the basic fluids, but again, the PS fluids are usually just heat and oxidation resistant, but otherwise a lower grade spec. On tractor power steering systems where the PS pump has a bad front seal, and is leaking fluid into the engine oil system, It common to just put the req engine oil in the PS reservoir, as it will end up in the engine slowly over time. BUT NEVER put engine oil in a trans system with wet clutches or wet brakes or expect the system to slip, and burn up the discs from slipping. Old spanish tradition.

Cat spec'd 10w motor oil in transmissions for decades..

 

[dhermesc]

Back in college - LONG time ago I had a Mustang that kept leaking PS fluid. I was always near broke and I stopped at WalMart to buy some oil to refill. I noticed transmission stop leak next to the ATF oil so I bought almost a quart of stop leak and filled the PS reservoir. Lost a little the first week but it did stop leaking. Topped it off with more stop leak (Blue Devil?) and drove it that way problem free for years. The stop leak actually looked thinner than oil but it worked.

 

[cumminstinkerer]

@dhermesc I just recently put Lucas PS stop leak in my 97 dodge diesel, it was loosing fluid somewhere, no idea where, and would whine and growl and barely work along with the brakes when cold, drained it out put a quart of the Lucas stuff in and so far so good, it's only been a couple weeks but!