Power Steering Fluid Change

Hi there

I want to change out my steering fluid, how many liters do I need to do a complete flush, I cant find the capacity of the steering fluid.

It also states to use mercon or mercon equivalent in a 1999 windstar, I am pretty sure I can use mobil 1 mercon, Am I Correct?

Also, Do I need that vaccuum pump to purge the system like alldata states or do I just turn the steering wheel back and forth once the fluid change is done? And do I keep the resevoir lid on when I am trying to purge the system by turning the wheel from stop to stop?

Thank you

DTF

just pull the return line off remove cap let it drain fill it back up (around one quart) turn it all the way right and left a few times recheck the level reinstall cap and thats it. if you do this two times you can get mostly all new fluid into your system

Ford does have an entire procedure devoted to flushing the PS on the Windstar.

Don't take what I'm saying here as definitive. Too much in the Ford procedure for me to retype but I'll give you the gist.

- remove fuel pump relay
- disconnect PS return hose
- plug the reservoir where the return hose was
- add an extension to the PS return line into a bucket
- raise the front wheels off the floor
- fill the reservoir to the right level (?? doesn't say if cap should be on or off ??)
- - IMPORTANT - -
- turn the wheel from stop to stop while cranking the engine until the fluid runs clear. DON'T CRANK FOR MORE THAN 15 SECONDS AT A TIME AND ALLOW 1 MINUTE BREAKS IN BETWEEN
- lower the vehicle, hook everything up, fill fluid
- start engine and turn wheel from stop to stop
- if PS pump is noisy, do the vacuum pump purge procedure

That's a good outline of it. I would suggest though, that if you see a bunch of junk in there when you empty it, and you've never done the procedure before, you may want to perform it again after driving the car for some time (like a day or week). I've heard these can get really gummed up!

Someone on here also suggested a synthetic fluid that can take the heat better. Anyone??

I would say that the Mobil 1 would be great for your power steering, it is a synthetic, and very easy to find.

YES the synthetic is better for heat......and also better cold flow for winter.

When you follow the FORD process (basically what I did), the resevoir will empty VERY fast....so just a light touch on the starter is all that is needed.
You do NOT want to crank the engine with the resevoir empty, as that will get air into the system.
If you just run it low, stop, and add fluid, crank again, add fluid, etc, you will avoid getting a bunch of air into the lines.
You will STILL want to do the air purge when done.

When you fill the resevior for the last time, and want to purge air, you DO want to have the cap in place.
Then, recheck the level.
With the fluid at the correct level, put cap on, run engine and turn the wheels from stop to stop.
When you recheck the fluid level, if there are a lot of bubbles in the fluid, wait a good while for them to rise to the top before running the engine again......or you will just pump the air bubbles back into the lines.

Hi, thank you to all that replied, this forum is just awesome, saving me soooooooooooooooooo much money than going to the ford dealer.

I just want to know when I am purging the system with the cap ON, once I have turned the wheels back and forth, should I turn off the engine to check the fluid or should I leave the engine running and check the fluid

Thank you alll once again

DTF

Hi Wiswind

you say "When you recheck the fluid level, if there are a lot of bubbles in the fluid, wait a good while for them to rise to the top before running the engine again......or you will just pump the air bubbles back into the lines."

Once I see the bubbles at the top should I turn the steering wheel from stop to stop until all the bubbles are gone or once the bubbles are at the top does this mean all the air is out???

Thank you

I just did this as well on my 145K miles 98 windstar after reading this and other posts about how windstars can overheat the ps fluid. Sure enough, mine was burnt smelling. I followed mustangmike's procedure above and did not have any problems with bubbles or air or anything. I ended up flushing about 1.5 quarts to get rid of all the color and burnt smell and then filling. Steering was smoother and quieter after this. thanks for all your posts about this topic.

...Steering was smoother and quieter after this. thanks for all your posts about this topic.

Just wondering, did you have any idle problems when turning the wheel before the change? Many of us have reported a surge forward when turning the wheel at low speeds which appears to be a result of the steering load on the engine.

I was curious if you had that before and if you did, did it get better after the PS fluid change??

Hi Wiswind

you say "When you recheck the fluid level, if there are a lot of bubbles in the fluid, wait a good while for them to rise to the top before running the engine again......or you will just pump the air bubbles back into the lines."

Once I see the bubbles at the top should I turn the steering wheel from stop to stop until all the bubbles are gone or once the bubbles are at the top does this mean all the air is out???

Thank you
As for the air in the system with front end off the ground I kept turning the steering wheel back and forth almost end to end tell the bad sound went away. Kept turning 10 times after sound went away turned off van open cap saw the bubbles went inside about 10min with cap off. After 10min put cap back on started the process again about 10 more times. And no bubbles. Thats how I did mine, makes a mess though, used old radiator jug to catch fluid. Used brake cleaner on the belt area, got a fluid on the belt and pully. i used four quarts of ATF on the 2001.

Just wondering, did you have any idle problems when turning the wheel before the change? Many of us have reported a surge forward when turning the wheel at low speeds which appears to be a result of the steering load on the engine.

I was curious if you had that before and if you did, did it get better after the PS fluid change??

I can't say that I had noticed a surge while turning before I did, this, I can imagine that could happen. What I did notice was that the steering was easier, smoother and quieter. Also, my wife drives this most of the time and she usually keeps her foot on the gas so she probably wouldn't notice!

I can't say that I had noticed a surge while turning before I did, this, I can imagine that could happen. What I did notice was that the steering was easier, smoother and quieter. Also, my wife drives this most of the time and she usually keeps her foot on the gas so she probably wouldn't notice!
LOL My wife drives the same way. Turns in the drive way at about 25 MPH
Hits the curb hard every time. I told her she paying for the tires when the front in gets out of wack.. She flies over speed bumps so fast you cant feel them.:grinyes:

LOL My wife drives the same way. Turns in the drive way at about 25 MPH
Hits the curb hard every time. I told her she paying for the tires when the front in gets out of wack.. She flies over speed bumps so fast you cant feel them.:grinyes:

LOL. I always told my wife that she was saving her tires because she pulls into the driveway without slowing down mentioned and that she is only using two tires.