I remember there being questions about doing a power steering flush a while ago. Well, I just did two of them yesterday. Here's how I did it:
1. Jack up the front end to get the wheels in the air.
2. Remove the wheel on the driver side. I found the best access and visibility to the return hose through the wheel well.
3. Pull the connector on the fuel pump cutoff switch. You could probably pull the fuel pump relay instead. Start engine let it run until it dies and try starting again to make sure it won't run. I didn't do this last part and the van ran quite a bit, catching me by surprise and making a mess in the process.
4. Remove the return line and insert 3/8 plastic tubing. Use the spring clamp to hold it in place. You'll need 4-6 feet of line. Run the plastic tubing to an appropriate container. Plug the reservoir return port.
5. Fill reservoir as full as you can get it.
6. Have your lovely (or other) assistant crank the engine with the starter and slowly turn the steering wheel.
7. Fill the reservoir as the level goes down. You may have to stop cranking the engine. I couldn't fill it fast enough.
8. Keep pushing fluid through until it looks new.
9. Suck out as much fluid from the reservoir as you can and hook up the return line to the reservoir. Fill reservoir.
9. Crank the engine and turn the wheel lock-to-lock to remove any air that may have gotten in.
11. Bring reservoir to appropriate level.
12. Clean up the big mess you just made.

An improvement would be to run another line from the reservoir return port to the container (rather than plugging it at the reservoir), but keep it plugged until you get to step 9. Then drain the reservoir with this line before hooking everything back up.

This took me about an 1-1.5 hours (including cleanup) and used three quarts of Type F fluid. Beer consumption would not have helped the process as your hands will be so slippery from being covered in fluid that you couldn't hold onto one.

 

After you flush always add an inline filter to the return line.

WIX TRANSMISSION / POWER STEERING FILTER #58964
200 PSI WORKING, PRESSURE RELIEVED, MAGNETIC
CHANGE YEARLY OR 12000 MILES
FORD EQUIVALENT FILTER KIT #XC3Z-7B155-AA
FILTER ALONE #XC3P-7B155-BA

 

Excellent post Mikeman. Was there any noticeable difference in the pump or rack operation afterwards?

 

I too would like to know if there is a difference. I need to do my son's '90 T-bird. I will be doing it this weekend, and will post the whys and results.

 

I can't really say that there was much of a difference. Maybe a slight difference in feel, but it could just be psychological. But, I think the pump and rack will be much happier with clean fluid. I did a pseudo-flush two years ago and got the fluid cleaner, but it was nowhere near as clean as with the method I recently posted. It's amazing how bad the old fluid was after two years.

 

I did this today, Mikeman is right on the money for it clearing up the fluid. Took three and a half quarts, wife didn't know what stop to stop meant on turning the steering wheel. Also is easier if third person sits in passenger seat and turns the key. I cut the return hose under the radiator, and put the in line filter there. Cut the hose so I got rid of the clamped section. Put everything back together with 3 ratchet style clamps. Used five feet of clear hose, and a coupler for flushing hose. Plugged return tube from pump with nylon tip. Only mess I made is when the D... plastic bottle almost slipped out of my hand and I squeezed it, sending a gieser of fluid in the air

 

Did this have any effect on the whine that most Aerostars have in the steering?

 

It is quieter, my last change was around 100K, did the ole turkey baster thing, took me a couple of weeks. This fluid looked and smelled like old burned coffee so hopefully this will hold off any future problems as I'm at 160K. Also with the heat and moisture in the fluid I may have been foaming over. Still have a shudder with low speed right turns, but not as bad. Will check further, may be a bad spindle. I used Valvoline SYN Power Fluid. I'm beat, helped someone put a muffler on a Honda this morning. Changed the PS fluid and cleaned the engine on the Aero, got up to 101 degrees here.

 

where did you guys find the inline filter? i've tried many parts store here in canada. and just about everyone at the counter gave me a blank stare. i've seen it before, but have no luck in getting it.

 

i work at a shop and we have a powersteering flush service 69.99. i do them on my old fords at the house with a vac pump

 

Mikeman>great description and info, will use next time.

Aerovan> try Wix's contact page for Canadian retailer
http://www.wixfilters.com/contact/index.html

<!--StartFragment -->I use LubeGuard in my power steering units now, quieted the Aero's pump. Use their Honda specific additive on the wife's Honda, don't have to go to the Honda dealer and pay $14.95 qt for their imported rice wine ATF. took roughness out of pump and rack.

I would recommend using synthetic Mercon in the newer Aero pumps, more antiwear and antifoaming than the older type F. Have Mobil 1 syn in Aero and Valvoline Maxlife in wife's Honda w Lubeguard add.

http://www.lubegard.com/automotive/pwrstr_protectant.html

Beers and greasy automotive work hands, put the quarts of beer in bucket up on the roof of the van in the shade, run vinyl hose down to work area with closepin valve. works great but has been known to cause sleep and snoring.
Shade Tree mechanic.

 

Aerovan,
I used the same inline filter for both my tranmission & PS.
Fordboy49

 

I used Mikeman's proceedure and it worked great. Changed P.S. fluid at 80,000+ miles and I couldn't believe what came out. It was a putrid, foul smelling darkish stuff that could't have been good for the P.S. system. I didn't put a filter in yet as I didn't want to deal with return line access limitations, but I will check out the return line under the radiator maybe easier to get at. The steering did feel different (more feedback?) after the flush. Mine never had the whine that some have so that didn't change.

 

The NAPA part number is #1-8515 Bar code 6476626010 says "Transmission Filter" on box, was $22.56 If you splice the filter in under the radiator make sure you cut the hose, with pan under hose, with the spring clamps not the formed ends hose. BTW I have the 4.0 2wd with P.S. cooler. Thinking about what I did, I'd have the person behind the wheel turn the steering to the left stop while cranking then back to center and stop cranking. To give time to catch up on adding fluid. Do the same, turning to the right stop and back to center. Repeat till fluid is clear. Wouldn't of had any mess if I hadn't fumbled the fluid bottle.

 

Thanks for the part # for the filter. I'm putting together a file of all this stuff for future referance. As far as "fumbling the fluid bottle".....EEEEEWWWWWW. I can only imagine the mess. Mine was bad enough when I pulled the return line off the pump. I was sure I had ruined a seal somewhere as the van dripped fluid for a while. Of course I have the AWD version which is a bit of a stinker to work with.