What type of Power Steering Fluid?

Turboomni

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I did a search and didn't come up with anything definitive. My fluid is a bit low and had some ATF but resisted until I asked you guys. Sorry for the elementary question.
 
Don't use ATF. Chrysler even says in the FSM not to.

Buy the stuff at the local parts store that says "power steering fluid" on the side.
 
Don't use ATF. Chrysler even says in the FSM not to.

Buy the stuff at the local parts store that says "power steering fluid" on the side.

LOL! Simple as that Big John? Just universal type?
 
Thanks ,,I tend to get all confused with Toyota only antifreeze and only Honda that and Ford this .
 
I hate to confuse the subject but I have ATF in mine. I had mine rebuilt and filled it with power steering fluid, it bubbled up and wouldn't function properly. My retired Mopar mechanic friend said he only puts ATF in his cars. Changed it out worked great going on 3 years.

I used type F.
 
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If using ATF it has to be the newer Type IV or if you go "old school" Type F that was used in Ford Products. These two do not foam up like standard ATF does.
 
Well this is why I asked,,there are so many ways. I am just going with "Universal Power Steering Fluid" and hope for the best lol.
 
I use Sta-lube power steering fluid pre-1989 Chrysler and gold in color. When I first got the car and resealed the pump I needed fluid. While my Fords use Type F I wasn't sure about Mopar so I bought the Sta-lube fluid. That was in 2010 and never a problem or leak since then.
 
Well... In all the Chrysler products I've owned over the years, I've noticed that every time I've had problems with a power steering pump, the first thing I noticed was it was full of red ATF.

Both are hydraulic fluids with ATF having friction modifiers (for the clutches), detergents and additives for rubber seals. As I understand it, PSF is a non foaming SAE 20 hydraulic oil.

We've had this discussion before and the argument will go on ad nauseam. My personal experience from when I used these cars in high mileage daily driving and Chrysler specifying PSF will keep me from using ATF. PSF is cheap and easily available. I can see no logical reasoning not to use it.
 
The 1.06 PS pump runs at very high temp. Regular ATF boils, which cooks the seals. They simply melt down. Consequently, the pump will start to leak. Mopar Power Steering Fluid can stand higher temperatures than ATF. This is what I'm using:
20160830_175432.jpg
 
The 1.06 PS pump runs at very high temp. Regular ATF boils, which cooks the seals. They simply melt down. Consequently, the pump will start to leak. Mopar Power Steering Fluid can stand higher temperatures than ATF. This is what I'm using:View attachment 90705
Dexron III has a boiling range of 546° to 1139° with a flashpoint of 376° and a auto ignition point of 599°. You have one kick *** power steering pump. Lol. Above 300° at does start to degrade so it is a thought. I have always used atf but I do not have anything but Saginaw PS pumps and if I get a car with any other style I would change it first then put new atf in it.
 
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Above 300° at does start to degrade so it is a thought.

I think it starts to degrade at lower temperatures than 300°. From what I've read, it starts degrading and forming varnish on surfaces at 240°. By 300°, it's cooked.
 
I think it starts to degrade at lower temperatures than 300°. From what I've read, it starts degrading and forming varnish on surfaces at 240°. By 300°, it's cooked.

I would have to think so too. Why else do people need to put oil coolers on for their automatics if not to keep them from cooking it over the years and a shortened life span.
heatchrt.jpg
 
Old thread but hafta reply:
As a former auto trans test engineer, I can say there's a lot of misinformation out in the world. It's nobody's fault, it's just what we've been fed over the years and we regurgitate it.

Both are hydraulic fluids with ATF having friction modifiers (for the clutches), detergents and additives for rubber seals. As I understand it, PSF is a non foaming SAE 20 hydraulic oil.

We've had this discussion before and the argument will go on ad nauseam. My personal experience from when I used these cars in high mileage daily driving and Chrysler specifying PSF will keep me from using ATF. PSF is cheap and easily available. I can see no logical reasoning not to use it.
Yes - ATF is formulated for a vastly different purpose than PSF - ATF's greatest purpose is to have proper qualities for clutches to perform properly, and with good lifespan. How the ATF treats seals and bushigns/bearings is important, but meaningless if clutches cook prematurely. PS has no clutch material, and therefore PSF is formulated for the job *it* has to do. And likely with far fewer detergents as there is usually no filter in the PS system.
The 1.06 PS pump runs at very high temp. Regular ATF boils, which cooks the seals. They simply melt down. Consequently, the pump will start to leak. Mopar Power Steering Fluid can stand higher temperatures than ATF.
Dexron III has a boiling range of 546° to 1139° with a flashpoint of 376° and a auto ignition point of 599°. You have one kick *** power steering pump. Lol. Above 300° at does start to degrade so it is a thought. I have always used atf but I do not have anything but Saginaw PS pumps and if I get a car with any other style I would change it first then put new atf in it.
I find it difficult to believe that a PS pump is generating enough flow, or the gearbox enough restriction, to get the fluid hotter than what a torque converter does. Even if so, I am skeptical that it is boiling. You may be seeing entrained air, but that is *not* the same thing.

I think it starts to degrade at lower temperatures than 300°. From what I've read, it starts degrading and forming varnish on surfaces at 240°. By 300°, it's cooked.
Degradation of fluid is a function of temperature and time. Consider that the fluid temperature in your torque converter is always notably higher than the 'measured' temperature, which is generally recorded in the sump. If we were to measure temperature somewhere other than the sump, that temperature chart would have all of us taking a taxi straight to the oil-cooler store to put a 30k GVW cooler on our cars.

In my younger years I saw similar charts and thought if I could get my trans down below 175 it would be such a great thing. But years later, after working with knowledgable people (sorry txchange.com) I learned you don't want your fluid running that cool, as it's not in its intended viscosity range to perform its job to its best ability. Too hot is not good, but cooler is not necessarily better.
 
I had an ex police 89 Diplomat and it had a smal cooler at the pump.
I always used atf. But maybe a good idea to flush and put new fluid in, if it has never been done, it couldn't hurt.
 
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