Power steering fluid versus ATF Dexron

[par]

Hi,

my Tacoma calls for ATF Dexron II or III and I have been using Mobil 1 ATF.

Often I see a real good sale on high quality power steering fluid and would like to try it.

What exactly is the difference other than color?

 

[Ray H]

No color. Automatic transmission fluids are essentially very high quality hydraulic fluids with friction modifiers* to moderate shift quality. The FMs have no effect on power steering components. The only PS systems I'm aware of that have specific fluid requirements are Honda systems. For your Toyota, stick with what you're using. It not only satisfies the hydraulic and system seal requirments, it's probably better than just about anything else you might consider substituting.

*Type F (for old Ford ATs) has no FMs.

 

[PandaBear]

Even Honda's PS fluid is only a thicker one with additional AW added. From what I heard it is also synthetic. I checked the datasheet on one blender that provide both formula and that is the only difference.

 

[dkryan]

par:

I second Ray H's comments. I had a choice of P/S fluid or Dexron III ATF in my Infiniti (according to the manual) and I'm running Mobil 1 ATF with no problems, no regrets!

 

[mrpcar]

Porsche cars also calls for a special fluid....

Callde "Pentosin CHF 11 S", which is used on both of my 993 and 996.

Which I have no idea what it is.

One time I accidentally drained some from my 993 and I couldn't get some from the local Pep boys so I replaced it with standard PS fluid and couple of years later my steering rack developed a leak, I was curious if it had anything to do with that.

In any case I replaced the steering rack with a life time warranty unit from Autozone and filled the reservior up with regular PS fluid 50k miles ago... so far so good...

 

[Mickey_M]

"Pentosin CHF 11 S" is a synthetic base hydraulic fluid, used in Jaguar convertible top hydraulic cylinders, Audi and BMW power steering, etc, etc.

 

[acewiza]

I like using steering fluid as opposed to ATF because of the clear color. I don't do PS fluid changes/flushes on any schedule, just check it every so often and add/change when necessary. It is easier to detect the fuid getting darker after a few years. Add an ounce of LC and seems to last plenty long enough, no problems noted.