Question About Power Steering Fluid

[santafelexus]

I noticed many refer the ATF (automatic transmission fluid) instead of power steering fluid. I just can't understand. Does LS 400 use ATF instead of p/s fluid? What's the reason? thanx.

[Shadow]

Yep, use Mercon III ATF in Ls' power steering.

[santafelexus]

Yep, use Mercon III ATF in Ls' power steering.

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why not using p/s fluid? just curious...

[monarch]

why not using p/s fluid? just curious...

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For 35 years the Japanese (except Honda) have designed their Power Steering systems to use Dexron automatic transmission fluid whereas the American car makers have designed their systems to use a dedicated special Power Steering fluid. Using these American car oriented Power Steering Fluids in your Lexus is obviously risky because Toyota does not recommend them.

If this is hard to understand then pretend you are a 40 year Japanese citizen living in Japan who just purchased a Chevrolet Trailblazer to drive around in Japan. For 25 years you have only driven Japanese cars that used Dexron Auto Trans fluid in the power steering system. Now you own this Chevy and the owners manual says to use a special General Motors brand Power Steering Fluid. You wonder why the Chevy needs this special fluid and start asking your buddies "Why can't I use Dexron Auto Trans fluid in my Chevy? The only reasonable answer your Japanese buddies could give you is "Using Dexron Auto Trans fluid in the power steering system of your Chevy is obviously risky because General Motors does not recommend using ATF in GM power steering systems.

So you need to keep telling yourself "I'm driving an Asian car now and the products at my local auto parts stores are still geared towards

[ajg2business]

Which one is it I've seen on several forums that Dextron II / III ATF. I've been running regular PSF for a few months and did not know abut the Dextron II. So now that I know I will be flushing the system to the correct fluid. Hope I did not damage the steering system. I am also going to replace the Air Control Valve had a spell with blue smoke at ca cols start too.

[AzHotLS]

Any Dexron fluid will work:

http://us.lexusownersclub.com/forums/index.php?showtopic=66909&st=0&p=421639

[Leverenz]

OK. new question, if I may. I think a shop put regular power steering fluid in my '99 LS 400. The power steering is heavy and seems to stick, at times. What is the best fix?

[billydpowell]

OK. new question, if I may. I think a shop put regular power steering fluid in my '99 LS 400. The power steering is heavy and seems to stick, at times. What is the best fix?

If it was one of mine, I would flush and refill with ATF. a little wasteful but wise.