Changing power steering fluid? -P30

[legomybago]

Whats the best way way to drain the power steering assembly if you wanted to change out the fluid? I would like to do this to our P30.

[DaveVA78Chieftain]

Dodge manual does not say how.  Attached is the Chevy Manual Power Steering Flush procedure.  I would think it would be basically the same.

Hmm, just noticed you did say P30

Dave

[legomybago]

Thanks, yeah I need to do some service with the inlaw on the P30, The FMC has a stand alone style power steering pump (no hydroboost), after I changed the pump out, the bleeding 29' of power steering hoses was fun!! I couldn't get all the air out utilizing a standard power steering bleed procedure that would work with 98% of cars out there. So I took the return line off the power pump, capped the pump end, aimed the return line in the oil fill on p-pump, ran engine while a friend turned the wheels back and forth and let the system circulate.

[cncsparky]

"Remove the fluid return line at the pump inlet connector and plug the connector port on the pump. Position the line toward a large container to catch the draining fluid."

I have 4 connections at the pump.  Three are nipples and one is a tubing flare nut.  Which one is the return?  I know one of the hoses goes directly to the reservoir.  Two other nipples look like both could be a return, they are hoses with clamps.  The hose with the tubing flare nut on the back side of the pump I assume is pressure.   i??

[cosmic]

I don't want to get to far off topic, but just wanted some opinions on tranny fluid in the power steering pump. mine has had it in there for 9 years. It seems to work just fine. I believe the P.O. put it in there because it is thicker and the steering gear box doesn't leak as bad. (I always have a drip that comes from the gear box. very small one)
Any thoughts on the tranny fluid in there. i??

[DaveVA78Chieftain]

I have 4 connections at the pump.  Three are nipples and one is a tubing flare nut.  Which one is the return?  I know one of the hoses goes directly to the reservoir.  Two other nipples look like both could be a return, they are hoses with clamps.  The hose with the tubing flare nut on the back side of the pump I assume is pressure.

I would think the highest clamp type hose would be the return line you want.  The do show pictures of the hose routing in the Service Manual.

just wanted some opinions on tranny fluid in the power steering pump

From the Chevrolet Service guide:
Avoid the use of automatic transmission fluid in the power steering system since it does not contain the additives necessary for good seal life. In an emergency situation, automatic  transmission fluid can be used to "get home." However, it should be replaced with power steering fluid as. soon as is practical.

Dave

[DaveVA78Chieftain]

just wanted some opinions on tranny fluid in the power steering pump

From the Chevrolet Service guide:
Avoid the use of automatic transmission fluid in the power steering system since it does not contain the additives necessary for good seal life. In an emergency situation, automatic  transmission fluid can be used to "get home." However, it should be replaced with power steering fluid as. soon as is practical.

Dave

[cncsparky]

While I'm not sure of the differences of PS fluid vs. ATF, we have used ATF in PS systems in a pinch before.  The comment from the service guide is strange, since auto trannys have lots of seals in them.

[UK-Winnie]

I know there are some Ford systems which are built to use ATF and some which shouldn't.  I learned this with my '72 Mustang which had noisy steering when I got it, like a crunchy noise that got worse as it warmed up and I could even feel it through the steering wheel.

I could see it was filled with ATF so I changed it for PS fluid and the noise went away.  I remember reading at the time that ATF was OK for some of the earlier boxes but the '72 had something called a "slipper" pump which needed proper PS fluid.

[cncsparky]

Do an internet search for ' ATF vs power steering fluid'.  Lots of info. Apparently, lots of vehicles can use either or.   

[Froggy1936]

As i remember when power steering came out in the 50,s All they used was ATF.  then somewhere in the 60,s power steering fluid appeared ! Frank

[legomybago]

I have struggled my whole life with buying "power steering fluid"!! I've always used ATF, But I buy power steering fluid now, and Im not sure totally why Hm? who knows...Maybe it's like todays parents making there kids wear helmets when they ride a bicycle??? We didnt wear helmets?

[DaveVA78Chieftain]

The confusion is why, for a P30 at least, I used the actual Service Manual reference.

Dave

[Stripe]

The older ATF fluid from "the before times" unlike the new stuff had a different viscosity from todays. plus you have to look at what happens to PSF and ATF when they heat up.

[Froggy1936]

The early ATF was made using whale oil (had to stop useing that enviromentalist thing) Todays ATF is not oil. Look it up at wickipedia There is a lot of good info ! Fran k Hm?

[Rickf1985]

ATF is a 10 weight petroleum base oil with a lot of different friction modifiers in it. The "old" atf, which would be things like Ford Type F, Were the same base but without all of the modifiers. A lot of drag racers will use Type F in their race cars. It is the same thing as "Trick Shift" at half the price. I have never heard of the whale oil thing and find that very hard to believe. It has been dino oil as long as I have been around, and that has been a long time. W% As far as power steering goes, ATF is designed to work with clutches and pistons where power steering fluid is hydraulic fluid and works ordinary hydraulics with no clutches. ATF can be used in a hydraulic system for a while but it will affect the seals eventually.

Here is one for you to think about since we are discussing ATF. The transmissions in the HEMMT heavy equipment transport trucks used by the military are filled with 30 weight motor oil! That is specified by Allison for the military.