Contour Enthusiasts Group Archives Forums General General Type of Power Steering Fluid

Every brand Type F ATF that I have looked at has Ford spec ESW-M2C33-F on the label (at least what we carry does).

If you want to stick with Type F, I haven't found anyone who makes a synthetic. The highest quality brand Advance carries is Havoline (Texaco), but Autozone carries Castrol - that would be my choice.

I did an extensive search on the Net & Newsgroups on Type F ATF fluid, & saw where someone "claimed" to have asked Mobile if Mobile 1 ATF could be used in PS units that required Type F, & Mobile said "no".

Also, I read that the properties of Type F & Dexron/Mercon are quite different - viscosity, anti-foam, friction modifiers, etc. The web sites listing their types of trans fluids said to never mix Type F & Dexron/Mercon, but were referring to their use in transmissions. Also, PS fluid is supposed to be different from ATF fluid.

Most newsgroups posts that I read said to not mix or substitute PS fluid, Dexron/Mercon, & Type F in PS units, & stick w/what the manufacturer calls for.

So, Jim, are they just not up on this? I "do" respect your opinion. But as I said, why did Ford specify Type F as opposed to Dexron/Mercon?????

EO1702 - Mercon is a type of ATF used in some Fords - now mostly sold as Dexron/Mercon -available in reg & synthetic. You might want to do a search on the many discussions about using synthetic Dexron/Mercon fluid in the MTX-75 - Ford issued a TSB recommending it be used in all MTX-75 trans - *must* be used in 2000 model years.

MANUAL TRANS FAQ

I use & highly recommend the use of synthetic oils in everything.
It lasts longer, protects better, and has a wider operating range with much superior thermal breakdown resistance. Plus it flows considerably better which equates to less power lost to parasitic drag.

Mobil 1 ATF plus FM in the MTX-75 "cocktail"
Mobil 1 ATF in the P/S
Valvoline Synpower in the brakes (Castrol Lima and HD Ford Blue are great Dot 4's as well - Remember any previously opened can of brake fluid is considered BAD! Moisture is it's mortal enemy! Once opened - use it all or just recycle the unused left-overs!)

Type F ATF is Mercon that has very thick friction modifiers added to it to prevent frothing & to help the clutch packs bite. (in an automatic) It greatly raises your parasitic drag.

Chrysler's ATF+3 & now +4 is Mercon with "newer" blends of friction modifiers that works more efficiently.

Mercon 5 is the only "semisynth" ATF spec. However heavy emphasis on semi. Maybe 15% synthetic base. It is also not compatatible with any other ATF.

P/S fluid would be considered a very light hydraulic oil. Low tolerance to high pressure, will burn up fairly easy, and has very little resistance to high heat thermal breakdown. Hence why it is not used is most cars anymore.
ATF provides much greater protection and a range of operations it is an ideal hydraulic oil to use. Most manufacturers have been using ATF in the P/S system for many years. (decades)

P/S steering fluid may have worked adequately on the old fashioned, low pressure, gear box pumps; but technology, component size and design & performance have come a long way in 30 years.

I don't see why we couldn't use Mobil 1 synthetic ATF (or any other synthetic ATF). The main difference in type F and Dexron is the friction modifiers (for the clutches), which should make little difference in the power steering system.
Type F is an obsolete fluid anyway and any synthetic should outperform it in PS systems. The PS pump for Duratecs is mounted inside the "V" and gets little cooling other than the auxiliary tube cooler, so syn fluids seem like a logical choice.

Here's some tech info on all of the various types of ATF:

http://www.pzlqs.com/Tech/Bulletin//DomesticMarketing/ProductApplications/pdf/p44a.pdf

It says, as I'd thought, that Type F isn't friction modified, hence isn't as slippery as a more friction-modified fluid.

Which brings up the question of why friction modifier which makes the fluid more slippery would allow the synchros to work better, anyone know?

Brian

Friction Mod REDUCES the slippery lube(synth) as it does in an LSD with plates,thats how it helps the syncros...