2nd Gen Non-Engine/Transmission Power steering flush

[BakerJ]

Me effort to flush the power system this weekend did not go well. 188,000 miles on system - fluid that came out was extremely dirty. There are 2 return lines on back of pump: one appears to come from steering system and one from brake system. I pulled both return hoses (they are low on reservoir, and a considerable amount of fluid ran out of reservoir. I poured in fresh fluid as I had someone turning steering wheel which produced a good flow from the steering return line. Pumping brakes produced spits of fluid from the STEERING! return line, and I did get a few dribbles from the brake system return line. From the look of the fluids I'd say they should have been changed 100,000 miles ago. I ran 3 quarts of new fluid into the power stering pump to flush it out and refill it. No doubt this did a lot of good, but there is still considerable contamination in the system. Also, there was a lot of foam in the reservoir, steering, and brake systems, and they didn't function well until repeated lock-to-lock steering turns (truck was on jack-stands) and repeated brake applications returned the systems to a normal feel. What is the proper way to flush the Power Steering system?

 

[Vaughn MacKenzie]

Hi BakerJ, I think you did OK. Sounds like the only thing you did was maybe not feed enough lube back in as the old was pumping out so you got some air in it. That's why you saw foam and the brakes and PS didn't function well at first. No harm done.



The PS/BP fluid is the forgotten fluid. I make it part of my regular maintenance to flush the PS/BP fluid, but I do it every 30k and all I do is use a vacuum pump and suck out what's in the reservoir and replace it with new. It doesn't fully change it but doing it frequently keeps it pretty clean. While I'm at it I also flush my brake fluid to keep it flesh.



I use Valvoline semi-synthetic fluid for my PS/PB system. I hear Redline (I think) makes a full syn fluid.



Vaughn

 

[BakerJ]

Hi Vaughn - That little PS pump moves quite a bit of fluid - it easily got ahead of my uncoordinated fluid additions - kinda like my uncoordinate aircraft turns - and I had brake fliud blown all over the engine compartment and on my new fan belt, when my catch bottle overflowed. I did use synthetic fluid. I lke the idea of sucking the old fluid right out of the reservoir - that would make the job easy enough to do frequently as you do. Thanks for the suggestion.