Power steering system noise?

[timsrv]

For some unknown reason Toyota engineers decided to put a fine mesh screen inside the power steering reservoir. When the screen clogs up, as is common on a 20+ year old system, the result is cavitation at the power steering pump. Cavitation will make the pump noisy and / or the steering jerky............especially when the van is cold. The best way of fixing this is to flush the system, clean the filter, and put fresh fluid back into the system.

I'm not sure what the factory recommended procedure would be for this, but as long as you get the old out, clean the filter / screen inside the reservoir, and refill with new fluid you should be in good shape. I empty the system by pulling a pressure line from the rack, then start the motor and use the pump to spray it into a bucket or drip pan (warning this can be messy ). After it's all out, you may wish to put a quart of new fluid in the reservoir just to rinse things out. Leave your drip pan in place and let the new fluid puke out like you did with the old. Don't worry about letting the system run dry (it won't hurt anything).

The tough part in all of this is cleaning the screen /filter inside the PS reservoir. IMO Toyota was not thinking straight when they put that thing inside a reservoir that was not designed to be taken apart . It can be taken apart and cleaned, but since it involves bending metal tabs, you're probably only going to get away with it once or twice before another reservoir would be needed.

Here are some pics of a reservoir I took apart for cleaning of the screen / filter.



It's tough at 1st to unbend these tabs. I used a 90 deg scribe from the side to get them started. It takes some force and some patience, but once you get it to this point a large slot tip screwdriver will finish the job with ease.



This particular reservoir came from a salvage yard and sat around dry for a while. Yours will probably look a little different inside.


I used a big bucket and some mineral spirits paint thinner to clean. I poured the paint thinner in the bucket, then threw the parts in and sloshed it around. I took the parts out and blew dry with compressed air. I ended up putting the reservoir back in the solvent/thinner and I repeated rinsing/drying until I was satisfied with the results. That spot you see is a stain on the bottom of the reservoir (not junk on the screen).


Re-crimping the reservoir lid.


All ready to be installed.


When it comes to filling back up, Toyota calls for Dexron II (which is NLA), so Dexron III is the next best choice. Stay away form the newer Dexron fluids (like Dexron VI) as they are synthetic and may or may not be compatible. This is a recirculating system and is also self priming / self purging. This is nice because there is no need for any special care when refilling or servicing. Once the pressure line is hooked back up just start the engine and start filling the reservoir. The pump will suck the ATF easily. Pause every few moments and listen. When the pump stays quiet without you pouring, shut off the engine and top off using the dip stick inside the cap. Start the van again, turn your steering wheel from stop to stop (to get any errant air bubbles), shut off and recheck fluid level. Add more fluid if required and you're done!

If you are cheap and lazy, and only care about shutting up that noisy pump, an alternative way (short-cut) could be to forget about everything I just said and simply poke holes in the reservoir screen with a screw-driver . Of course this is defeating the purpose of the screen and you would be releasing all the grit previously captured back into the system. This method would also most likely shorten the life of your power steering system. Have fun. Tim

PS: Since you're servicing your power steering system anyhow, it might be a good idea to check the pump for leaks and repair (if required). Here's a couple of good threads on that:
http://www.toyotavantech.com/forum/s...-Steering-Leak
http://www.toyotavantech.com/forum/s...alot-of-fluid!
https://www.toyotavantech.com/forum/...-steering-pump

[Flounder]

There seems to be a fair amount of room beside the PS reservoir. Wonder if it's possible to put an inline filter in the PS pump suction line? It's plenty long. Have to look at doing that...

[timsrv]

Just keep in mind that this is a suction line and any restriction here will make the pump more prone to cavitation. I think that's why they put it in the reservoir (the best location with most surface area for a screen). It's just too bad they didn't make it easy to access. I'm not saying an in-line filter wouldn't work, I'm just saying restrictions on suction lines are not good. Tim

[Cornato]

I think my pump is leaking and it's noisy as hell and a little jerky when cold. So I bought the seal rebuild kit from RockAuto like mentioned in another thread. And am going to replace all the seals and clean out the screen and bleed it a few times.

If that doesn't fix it, then f*&k it. My first 2 Toyotas never had power steering. That's how I can crush pecans with my fingers.

Will update hopefully soon with progress.

[Spindrift]

I think I am going to try this. Where exactly is the hose you pull to drain? Not a 100% sure where the rack is.

[timsrv]

The rack is a few inches in front of the bottom of your radiator. These lines can get rusty and stuck so be sure to use a tubing wrench. If these lines are too rusted, rather than risk damage you may wish to forego the flush. The screen in the reservoir catches most of the particles anyhow, so just cleaning that should be good enough. Tim

[Spindrift]

I just realized I need to get that big expensive hose before I attempt this because I have a feeling mine will crumble.

Question: Is all ATF Dex II red in color? The reason is. My reservoir was really low so I put fluid in (ATF Dex II -red) and now when I check it it isn't so red. I think the stuff that was in there was brown because now I have redish goldenish brownish.

[timsrv]

Dexron II was red but is NLA. Dexron III supersedes Dexron II so use that. Anything running for 25+ years in a closed system will turn brown. A system flush is preferred but if you have stuck pipes on the rack I wouldn't worry about it...........just cleaning the filter should be good enough. Tim

[Spindrift]

Looks like some spam got in. Anyway it reminded me to follow up on my power steering noise. It turns out it was the alternator because when I replaced it the "power steering" noise magically went away.

[honeybadger]

Most high mileage vehicles seem to have a whiny power steering pump so maybe I should be used to it but it is highly annoying. Is there any way to get rid of the noise without a completely new power steering pump?

[foreverly]

It means you are not getting enough fluid to the pump either because

1. not enough fluid / you have a leak
2. a restriction in the system - a kink in a hose, dirty filter, a contaminated hydraulic system
3. air getting into the system - a hole in a return or reservoir hose allows air into the system.

With that said, I think the power steering systems on old Toyotas are a bit week. I've never had this level of power steering problems on any other vehicle I've driven.

[fuquan]

I think my pump is leaking and it's noisy as hell and a little jerky when cold. So I bought the seal rebuild kit from RockAuto like mentioned in another thread. And am going to replace all the seals and clean out the screen and bleed it a few times.

If that doesn't fix it, then f*&k it. My first 2 Toyotas never had power steering. That's how I can crush pecans with my fingers.

Will update hopefully soon with progress.

I have thought about running my van without power steering so that I don't have to deal with the leak - just drain the system, pull the belt and be done with it - but the steering rod and U-Joints look pretty small to me. On previous vans those U-Joints have even had play in them. Any thoughts on how much stress manual steering would put on the 25+ y/o steering linkage parts?

[timsrv]

That's a good point. Running without power steering increases stress on the moving parts ahead of the rack. These vans aren't known for heavy duty parts here. In fact, there was a recall due to gearbox failures. That being said, I've run these without power steering before and things seemed solid enough, but that just was a temporary thing. It's conceivable that running that way long term could create a safety issue. Tim

[toytime]

In a previous post I reported the PS hose was dry rotted and broke off in my hands… so why not search the forum for tips and Timsrv had a great post filled with instructions on how to clean the screen in the PS reservoir Tim if you read this you were right on undoing the tabs will make you want to take the easy way out but I kept my patience and it was well worth it, the screen looked like it had coffee grounds embedded in it also I didn’t undo the pressure line at the rack but I did empty the system when I removed the reservoir I simply placed a small jug in its place and collected the goop there no wonder the PS pump wines the fluid is like loose mud….. the rest went just as you said I’m glad I didn’t resort to poking holes in the screen Thanks for sharing your technique. Ralph

[Burntboot]

I did this same thing a couple of years ago but when I looked at the lines at the rack there was no way in hell I was going to disturb that mess of rust and scale. I did flush the system but did it a little differently.

I took the feed hose to the reservoir and re-routed it into a large waste jug.
The suction hose got routed into a large jug with fresh fluid.
It was a little messy but worked well enough and saved the headache of messing with the hard lines.
BB

[timsrv]

I keep forgetting that some of these vans get messed up with rust here. They don't salt the roads here so my vans typically stay pristine in these spots. Tim

[Burntboot]

Sounds like paradise to me.
I can't imagine what it would be like to live in a place where things don't rust.

I live in a land where most cars do well to see their 10th birthday and 15 is considered "ancient".
I can count the number of pre `95 DD's around here, on one hand (and 3 of those are mine).
BB

[timsrv]

Most people around here dump cars after 10 - 15 years too, but it's not because of rust. Usually it's neglect or them just wanting something new. Like the 06 XB I checked out on Saturday. Had 95k miles on it & still the original coolant . I'm guessing the gear oil was original too. Tim

[Usaviator]

Im in a little bit of a bind here. This problem started out when I accidentally added oil to my power steering reservoir. Luckily, it didn't take much at all before it was topped off, and something raised a red flag in my head and checked the manual and UGGGH wrong one. I'm also lucky I never started the engine. I removed the reservoir, completely cleaned it out of all gunk. This actually turned into a good thing and now my reservoir and screen is nice and clean. However, I was reading about what kind of fluid to add to the reservoir. Tim, you recommended Dexron III, but this post was from 5 years ago. Now I guess you can't find Dexron III anymore (at least according to the guy I talked to at autozone). He did say that Dexron IV was in now and they make synthetic and mineral versions of it. My bind that I'm in now is that I need to get to work and this is my one and only vehicle. I am going to head to autozone and pick up the Dexron IV. You had mentioned to stay away from Dexron VI (6). Did you mean Dexron IV? Under the time limit I am currently under, I need to get something to put in there. The Dexron IV mineral seems like my best bet for now, so I'm going to add it. If you think its a bad idea though, I may end up draining the system and refilling it with something better. It can't hurt to flush it anyways eventually, but let me know if you have any input on this.

[timsrv]

If there is a Dexron IV, then I'm unaware of it's existence. Of course I buy in bulk and only buy every 5 years or so, so things could have changed. I am also unaware that Dexron III has been discontinued and seriously doubt that it has........but again, I could be wrong. Whatever you purchase, just make sure it's backwards compatible and will mix with Dexron II & III. Tim