Power steering flush after noise

[cary]

When driving this weekend on a very windy road I noticed that my power steering started to whine a bit and was vibrating a bit. I have been putting off flushing the fluid (148k miles 1996) but when I got home and checked it, found the fluid had gone from slightly brown to obviously overheated and nearly black. I am guessing the back and forth on the steering wheel pushed the fluid over the edge and overheated it. So last night, I decided to flush the fluid using RavenTai method.

The fluid that came out was not red, not brown, but black. I ended up using almost two quarts of Redline D4 ATF in the process of the flush, running it through until the fluid came out bright red. The pump is definetely running a bit smoother now and isn't whining as much. I am going to see how it does and may try the Downey trick if it gets any louder again.

In short, you may want to do this 40 minute 1 job if you haven't. I may have damaged the pump by leaving the old fluid in there so long. You don't have to use synthtic ATF, you can use mineral ATF and do the entire job for less than $5.

 

[concretejungle]

Cary, i'm glad you had success in this. But, i must post that others have not been nearly as successful including myself. My PS fluid looked pretty bad, but my pump wasn't groaning. So i figured good preventative maintenance meant going ahead and flushing it out. So i did and replaced with M1 syn. ATF fluid. Ever since the flush i have had issues and groans from my PS pump that will not go away. Was it the flush that did it? I don't know, but i do know that it was perfectly fine until i messed with it.

 

[cary]

I can understand the concern. It seems to be one of those issues where it isn't always clear if one should be done. A compromise could be to simply baster out some fluid at each oil change and add some new mineral ATF. I figured after mine started making noise and vibrating, I had little to loose by flushing it.


BTW, when the power steering pump fails what usually happens? Do you get a nice explosion with oil all over? Does the power steering go out? Does it just get so noisy that people think you have cat stuck in there?

 

[e9999]

used some dino chevron stuff.
groan disappeared!

 

[7P's]

BTW, when the power steering pump fails what usually happens? Do you get a nice explosion with oil all over? Does the power steering go out? Does it just get so noisy that people think you have cat stuck in there?

When your power steering unit fails all you'll have left is "Armstrong" steering and you will be able to tell the difference, especially when you're stopped and attempt to turn your wheels. While driving down the road you won't notice the difference until you slow way down and start a turn - takes a little effort if you have big tires.

 

[Tools R Us]

Noises can be from bad bearings, low, old, wrong type fluid. Most pumps die from seal failure, heat causes the seals to harden and loose their ability to seal, resealing them is a relatively easy job.

I am not totally sold on the selection of ATF for power steering systems, it seems like a compromise at best. ATF has detergents, friction modifiers and conditioners to deal with the clutches in the trany that aren't needed in a power steering system. The power steering system is a pure hydraulic system, I am thinking about changing to something like Mobil DTE light, it's a good clean hydraulic oil with antiwear agents. The factory fill looks to be hydraulic oil, not ATF.

My observation has been every Toyota 4x4 pump that I have rebuilt has failed due to seals hardening. This is from heat, I don't think the cooler is sufficient for slow speed wheeling in hot conditions. The seals are rated to about 215F, if they are heated more than that they will harden and crack, this is the type of failure that I have seen when disassembled. If oil is used that hot it will quickly breakdown, turn black and raise wear rates.The simple fix is a larger cooler, but oils work best at about 180F if too large of a cooler is used the system will run too cool, that can be harder on components than too hot. Probably a bypass thermostat controlled cooler or a cooler that is mounted out of the airstream and cooled by a thermostat fan, would work best for both high heat loads of slow wheeling and relatively low cooling needs of high speed highway cruising.

 

[concretejungle]

Thanks tools, may i have another?

 

[Rookie2]

I am not totally sold on the selection of ATF for power steering systems, it seems like a compromise at best. ATF has detergents, friction modifiers and conditioners to deal with the clutches in the trany that aren't needed in a power steering system. The power steering system is a pure hydraulic system, I am thinking about changing to something like Mobil DTE light, it's a good clean hydraulic oil with antiwear agents. The factory fill looks to be hydraulic oil, not ATF.

FWIW, the FSM is pretty clear on using Dexron II or III ATF. I guess I'm not smart enough to second guess it. I flushed mine at around 75k with regular $1 a bottle ATF and haven't had any problems (knock on wood).


Rookie2

 

[cary]

When your power steering unit fails all you'll have left is "Armstrong" steering and you will be able to tell the difference, especially when you're stopped and attempt to turn your wheels. While driving down the road you won't notice the difference until you slow way down and start a turn - takes a little effort if you have big tires.

Agh, it will be like the good old days!!! I have never had one fail before so I didn't know the normal mode of failure.

 

[Hayes]

I was getting groans a while back. I flushed with (RT method) some cheap ATF, and filled with MaxLife ATF (dino). Tools' comments about hardened seals makes me feel even better about using an ATF with a healthy component of seal conditioners.

Things have been smooth and quiet ever since.

Hayes

 

[landtank]

So Tools, I have a hydraulic winch plumbed into my PS system and have been wondering if there is a better fluid than ATF for my purposes. This mobile dte going to be a good thing on my truck? If so where do I find it?

 

[Tools R Us]

I haven't tried it, yet, but believe it would work well. Mobil DTE 24 is a light hydraulic oil, ISO32, SAE10, about the same viscosity as ATF, it has very good antiwear and antifoam/cavitation additives. Most of the time it's cavitation that causes the groan in power steering systems. It's used in everything from heavy equipment to CNC machining equipment, in the hydraulic systems and in spindle lube applications. I buy it in gallons locally from a machine shop supplier for about $15.

http://www.mobil.com/USA-English/Lubes/PDS/GLXXENINDMOMobil_DTE_20.asp#TypicalPropertyTitle

http://www.use-enco.com/CGI/INSRIT?PMAKA=505-1210&PMPXNO=945277&PARTPG=INLMK32

 

[landtank]

It just dawned on me, Grainger's. They have it listed on their site And I'll pick some up if available and have it in this weekend hopefully.

 

[elmariachi]

I have read of these pump failures since I joined Mud. Of the 6 80s I have owned, I have been fortunate enough to not have any. What I do is use the baster method with a 10CC syringe. When I get a truck, I suck about half the reservoir out and replace it with clean ATF every couple weeks until its red. Then I do the same every month or so as PM.

 

[landtank]

Tools, from the Grainger site it would look like the DTE 24 is what you're talking about. DTE 26 is heavier.

 

[Tools R Us]

Your right, I have a bottle of each here, 26 is medium, I will edit.

 

[IdahoDoug]

Tools, Nice writeup on the PS stuff.

Jim, I also do that with the turkey baster. This is a nice low stress way to replenish the PS system additive package without the danger of kicking junk loose in a flush, OR putting air in the system.

I also had mine start groaning out of the blue a couple years back. I posted a way to improve a bit on the factory manual technique. IIRC, I had the groan for a couple days after on a fast diminshing scale that disappeared and has not come back.

I think it's Cdan who got some of the original factory fill and that's what he uses. I think he called its color 'blonde' or somesuch. Hmm, that may have been a different thread....

DougM

 

[whodat]

Is it okay to mix power steering fluid and atf? I want to use the turkey baster method but I want to switch to atf.

 

[Tools R Us]

I don’t like mixing fluids, but Toyota recommends ATF for top offs, so it must be compatible.

 

[e9999]

I'm wondering if the baster method is as effective at removing sediments and crud as the pump by turning method...?