Royal Purple ATF in Ford PS pump

[OVERKILL]

I had 6 litres of Royal Purple ATF that I got a while back that I traded a pair of used tires off my Mustang for (I no longer owned the wheels they came off of) and I knew the Lincoln was due for another PS pump flush.

BUT, I only had like 1/8th of a quart of my normal Mobil 1 ATF that I use....

Figured what did I have to lose? So I used my vacuum pump to drain the reservoir and filled it with the RP ATF.

I could be hallucinating, but it seems even quieter than with the Mobil 1 ATF in it! I was somewhat surprised.

We'll see how this stuff holds up in terms of noise control.

 

[simple_gifts]

I guess "M1 makes my car noiser" has moved into a new realm....

 

[OVERKILL]

I'm just going to clarify here:

M1 makes the Ford PS pumps MUCH quieter in my experience. Especially the EEC-IV era cars/trucks. If you have any experience with older Ford's, you'll know the noise I'm talking about.

What I'm saying in my OP is the RP ATF seems to have made the PS pump even quieter still! (we aren't talking a HUGE margin here, just an audible difference) Will it STAY quieter? I'm not sure. It could be just swapping it out for some fresh Mobil 1 ATF would have yielded the same results.

 

[wander2039]

Have a 06 Ranger and noticed the same with M1 and RP. No real difference in our 04 Escape though.

 

[Jim Allen]

FWIW, I used RP power steering fluid in my old '86 F-250 and it was quieter at the locked positions. No more buzz. Put it in my 10K miles F-150 for it's first change and didn't notice anything different... it's a rack and pinion system, tough.

 

[OVERKILL]

This was their ATF (being used as PS fluid), not the PS fluid. I would imagine there would be at least some difference in formulation.