PSF instead of (obsolete) Mercon in a PS system.

[mrsilv04]

I goofed. After a repair, I used power steering fluid in the 2003 Ford F53 (Class A motorhome chassis), instead of the (obsolete) Mercon that it specs. All of my daily drivers use PSF, and I just grabbed PSF without taking a moment to think "it's a Ford".

I would assume that the system is majority PSF at this point. The fluid in the reservoir has a just a slight pink tinge, instead of the dark red color that pure ATF would have.

Should I plan to flush/drain, and replace with ATF this weekend?

Most worried about the affects of having ATF in it for 12 years, and then the switch over to PSF might cause... leaks, noise, PS pump failure?

 

[michaelluscher]

I've had good luck with Maxlife ATF in quieting Ford pumps

 

[qdeezie]

I'd just flush it out and go with Supertech D/M. Works just fine in my Ford. I'll eventually be going to Syn, but I have no need to rush.

 

[SuperDave456]

I've also had good luck with Maxlife in Fords.
I'd do a few turkey baster drain and fills and call it a day.

Most PS systems aren't picky.
In older worn Fords, like my 2002 Taurus with 208k miles, I've had luck with Maxlife. That quieted it a bit, added some liquimoly MOS2 and a small bit of Rotella T6 5w40 synthetic to thicken it. It went from noisy when hot to quiet all the time.
Not worried about below zero here in Texas, and even then the Maxlife is a 20weight synthetic.

I've played with Ford PS pps enough to know that they aren't pickey.

 

[Yah-Tah-Hey]

Valvoline makes a Dex/Merc ATF that works in the PS systems calling for Dexron II/III. Maxlife is also a good choice.

 

[CorvairGeek]

If it was me, I would remove the return line at the bottom of the reservoir to drain and refill the system a few times, refilling it with what ever Dex/Merc you choose (or even see what Ford now recommends) . The steering pump (ZF made) and steering box (Bendix made) are typically not Ford products on the F53/F59 series (I realize yours is newer than my 1995 I've had since it was new), so what anecdotally works for standard Ford products probably isn't applicable. As the brakes are hydraulically boosted on the F53/F59 as well, there could be a lot of collateral damage I would not risk.

 

[buck91]

I had a 94 Crown Vic with almost 200k on it and a slight PS leak. I bought a gallon of cheapo PSF and kept topping up with that for a few years without issue.