Power steering fluid type?

[4RrDriver]

Generic PSF isn't really that special of a product. The vehicle specific stuff I'm sure is intentionally formulated for a specific system. But generic stuff is, if I recall, just mineral oil. ATF has detergents, seal conditioners and friction modifiers. I believe it's a superior lubricant - particularly the newer synthetics.

The Valvoline Maxlife ATF that I used has an advertised pour point of -48c. It gets down to -40c (also abot -40f) in my area and regular fluid is as thick as tar. It can be difficult to turn the steering wheel for the first few miles until the fluid warms up. That's really hard on everything in the system - the pump is straining to push PSF that's nearly solid, the seals and hoses are experiencing extreme pressures they weren't designed for etc. I have blown power steering seals out of a rack and blown high pressure lines on other vehicles when on cold mornings, I simply pulled out of the driveway.

Synthetic ATF is not only a good lubricant, it stays much more viscosity stable through a range of temperatures hot and cold, providing less wear.

 

[inscarguy]

Sorry to rebump an old thread.

I did the power steering pump about 4 years ago on my 06. Even though it says ATF I used prestone asian synthetic PSF.

It now has 138000 miles, dead quiet, no leaks, perfect steering feel.

In my 08 I changed the pump and used ATF. Its noisy, steering feels a little looser and its louder on start up.

Like Blackworks said power steering fluid is basically ATF with added conditioners and anti foam agents.

I am going to flush out the ATF out of the 08 and use the PSF.

 

[firebirdguy]

Sorry to rebump an old thread.

I did the power steering pump about 4 years ago on my 06. Even though it says ATF I used prestone asian synthetic PSF.

It now has 138000 miles, dead quiet, no leaks, perfect steering feel.

In my 08 I changed the pump and used ATF. Its noisy, steering feels a little looser and its louder on start up.

Like Blackworks said power steering fluid is basically ATF with added conditioners and anti foam agents.

I am going to flush out the ATF out of the 08 and use the PSF.

so the toyota engineers were wrong for specifying dex2/3? if PSF was the same as ATF, toyota would have said that either was ok.

the issues you describe in your 08 are most likely due to the change of the pump, not the ATF itself. aftermarket p/s pumps are notorious for not working or being noisy compared to original OEM pumps... on any make of vehicle.

some p/s systems are designed for ATF, some for PSF, some for brand specific fluid... yes other fluids will "work" since they are all hydraulic fluids & wont cause a catastrophic failure, but i prefer to stick with what the engineers designed the system to use.

 

[inscarguy]

Are these the same engineers that designed the v8 exhaust manifolds that crack, the ones who designed the wonderful seizing calipers, the ones who designed our uncomfortable seats, who designed an airpump that fails and put it under the intake yet does not warranty them but all the other vehicles that have 4.7s are covered. I could keep going.

I replaced both pumps with OEM. there are certain things I only use OEM.

So you dont use synthetic fluid anywhere? Engineers designed our vehicles to use conventional fluids yet synthetics are superior. most everything in a vehicle can be improved on. As I said before ps fluid and dextron are interchangeable. On most vehicles if you run low on ps fluid, trans fluid is an acceptable replacement.

Ps fluid has additives that will make the system operate better yet trans fluid will last longer so it would help with longer maintenance.

This argument could go on forever its all up to what the owner is comfortable with.

 

[Toyojay]

I've always used Dex III on my toyotas, occasionally I'll top off with TIV if thats all I have. Very close fluid to Dex.

DexIII can still be purchased at the dealer, its just called "Automatic Transmission Fluid" but its just good old DexIII. It can also be purchased from any GM dealer, or place that sells ACDelco fluids, in the AC bottle it's just called "Manual Transmission Fluid" all the same stuff.

 

[firebirdguy]

Are these the same engineers that designed the v8 exhaust manifolds that crack, the ones who designed the wonderful seizing calipers, the ones who designed our uncomfortable seats, who designed an airpump that fails and put it under the intake yet does not warranty them but all the other vehicles that have 4.7s are covered. I could keep going.

I replaced both pumps with OEM. there are certain things I only use OEM.

So you dont use synthetic fluid anywhere? Engineers designed our vehicles to use conventional fluids yet synthetics are superior. most everything in a vehicle can be improved on. As I said before ps fluid and dextron are interchangeable. On most vehicles if you run low on ps fluid, trans fluid is an acceptable replacement.

Ps fluid has additives that will make the system operate better yet trans fluid will last longer so it would help with longer maintenance.

This argument could go on forever its all up to what the owner is comfortable with.

big difference between a part or system being designed for a specific type of fluid than there is a part failing or a seat being uncomfortable...

brake calipers seize mainly due to climate, winter states have far more seized calipers than southern & western states, my 08 sport has original calipers doing fine at 145k, in iowa!

my seats are very comfortable compared to other vehicles ive owned or ridden in, thats all just personal subjective opinion.

exhaust manifolds can crack mainly due to poor metal content during casting, happens on many vehicles, its not the engineers fault that designed them. & again, that doesn't really pertain to using a different fluid than whats called for. i could keep going too.

yes i use synthetic fluids, 75/90 gear oil is only offered in synthetic, i also use synthetic oil when the factory doesnt specify either type, but oil is oil regardless of the base oil type.

the p/s system calls for a specific fluid, dex2/3, yes you can use a synthetic like maxlife that is still dex 2/3 compatible. but using PSF is not what the p/s system is designed for, otherwise toyota & many other companies would say use either or. & the whole, "PSF has additives to make the system operate better" is a myth with no proof, ive read the same for ATF, got any actual documentation to back up that claim? ive probably read just as much on that subject as anyone & there is no proof either is "better"... it comes down to what the manufacturer says to use, & nobody on here is an engineer for toyota, so why question or try to redesign what they say?

as for OEM parts, todays replacement OEM parts are not the same as wht was installed when the vehicle was made. do a search, there arre plenty of comments of people saying teh OEM calipers are not the same as the original installed ones. in the world of muscle cars, parts like ac delco are NOT what they originally were, same applies to most OEM replacement parts these days.