1999 Econoline 4.6

I have been bouncing around these forums looking for infromation about replacing the power steering fluid. I have a leaky high pressure power steering line and will be replacing it.
I gather I use Mercon Automatic Transmission Fluid.
I need about 4 quarts

But why do all the Flushing posts here mention pressing the brake pedal while flushing the power steering system? Are the two systems connected somehow?

Thanks In Advance.

Pete

 

On a standard van without Hydro-Boost brakes there is no connection between power steering and brakes.

 

On this van, there is none. A lot of diesels use a hydro booster fed off the power steering pump for the brake pedal instead of a vacuum booster (diesels don't make vacuum). The flush procedure for your van is pretty straight forward. Ford says to disconnect the PCM relay so the van won't start, unhooking the return line to the reservoir, and putting it into a drain bucket. Raise the front end of the van. Crank the engine over, and turn the wheels from stop to stop (making sure the reservoir doesn't go dry). Reconnect everything and start the engine, take the wheel from stop to stop again.

 

Thanks guys.

I never thought about diesel not having vacuum but it sure makes sense.

So I learned something today in addition to details about flushing.

Love this fourm.

Pete

 

Well I really do have a Diesel.........435k and counting.......and believe me ..when you have no Vacuum you have no brakes....at least not power ones.....I think the last time I changed the Vacuum Pump was 5 years ago....BUT in your case as stated before there is no correlation between the two.....I would use synthetic ATF and watch for foaming.....Theoretically if it foams a lot it means you have water in the system or your Pump is toast....(It is called Cavitation ) I have never seen it ..all the pumps I ever changed had bearing issues or other leakage.....SO ....... In my opinion do not overthink it....and deal with the scene as it arises....The Ford Pumps are pretty Good..The old Saginaw ones were Bulletproof...So just scan Ebay for a new one...I think I paid 50 bucks for my spare....(.FORD OEM ..they called it New Old Stock )..I have like 5 old Saginaw ones...with the specific engine bracket assemblies ( Read 460/400M/300 I6)....This is my 8th Econoline......I still have parts for the old ones......

 

Well, I finished. In my case is was a leaky pressure tube right at the fitting going into the steering box. It just rusted out. A new one was $22.

The main problem I ran into was getting a wrench on the line at the pump. The pulley left me only enough clearance to get a 11/16 open end wrench on it but the angle was such that I couldn't get enough force to loosen the fitting.

Finally I said go whole hog. I cut off the tubing at the fitting with a dermal tool. Then I could put a 18mm deep dish socket on the fitting and it came right out.

It took about 2 qts of Mercon to flush and fill the system. Most of that I recovered. I don't know if I should save it or what. It is ruby red and no bubbles. I used BoKnowsDiesel's method. As he said, that is how the manual recommends. (I have a CD of the manual)

In case anybody stumbles across this thread I should add that at first, as I turned the wheel left and right the fluid came out (I had a clear vinyl tube into a translucent 1 gallon container) near the ends but the tube went empty as I turned through center. I kept turning left top right and after maybe 20 or 30 turns (I only cranked for 30 seconds then took a break) the fluid flowed continuously.

Looks like I'm home free.

Thanks again and I hope this helps someone else.

Pete