Why use ATF as PS fluid?

[elwesso]

I had to top off my PS fluid the other day, and when i got my fluid flushed they used regular PS fluid instead of ATF.... I have been told that its just as good as ATF... however, why would anyone use ATF instead of PS fluid, which I dont think breaks down quite like ATF (as fast).... I wont be changing my fluid for a while, as its still good......

When i took my car in to get it done, they said most times that doesnt need to be changed.... Most cars however use the PS fluid... So why would anyone use ATF if it needs to be changed and breaks down, and not use PS fluid which doesnt need to be changed.....

[Q451990]

So you're saying you're using PS fluid and not ATF right now???

I'll let others weigh in here, but I'd sure get that stuff out of there before you drive it again. From what I understand the seals, pump, etc. are set up for the specified fluid, and there's a lot of difference between the two!!!

Might need to save for a steering system overhaul instead of the new interior you've been talking about

Heath

[autotech43]

That particular question came up one time at the training center. Here is what they told us. Nissan/Infiniti power steering fluid have basically the same properties as the Nissan D type fluid (dex fluids). The color is different to determine where a leak is coming from if one occurs. You have to remember that the pump seals, pump itself, and the rack and pinion seals are of the same material as in the Nissan/Infiniti automatic transmissions. I took it one step farther and ask engineering about this concern, if you have a complete empty power steering system, you can use either ATF or the P/S fluid. They do not recommend the mixing of the two. Now we ARE discussing Infiniti/Nissan type vehicles, whereas I think some of the other manufactures dont even make a specific P/S fluid and suggest only using ATF. But discussing those other type vehicles can open up a BIG can of worms.

[Altiman94]

ATF keeps the system clean.

[Q45Viper]

I would always go with the originally suggested Infiniti schedule of fluids unless one of our gurus such a Dennis says otherwise.

[elwesso]

Well it has been COMPLETELY flushed (2 or so times) with the PS fluid.... I will still change it in about 15-20k or whatever the recommended interval is... Then Ill use ATF.....

BTW this was the off the shelf kind of PS fluid if that makes a difference....

[90Q45blue]

That would definitely make a difference and not a good one. As autotech said, the Nissan/Infiniti p/s fluid is different from your off-the-shelf brand and is very very similar to ATF.

In short: if you're going to use P/S fluid over ATF, ONLY get the Nissan brand.

Nick