ToyotaLexus

I used a fluid evacuator and sucked out all the power steering fluid my RX's
power steering fluid reservoir a few days ago. The fluid inside was the original
fluid that came with the car and it looked dark and nasty...

After the reservor was completely empt, I filled it with Mobil Synthetic ATF,
which is the dark red/pink ATF color.

I checked the reservoir again today because I planned to suction the fluid
out for a more thorough change.... but to my surprise, the ATF fluid inside
the power steering fluid was still very clear... exactly like the new ATF fluid
that I poured in a few days ago.

Is the fluid inside the power steering reservoir supposed to circulate with
the fluid inside the power steering system? Or does reservoir only serve
as a reservori? (like the coolant reservor?)

thomas1

Mine definetely circulated, especially after turning the wheel hard left and right. I had to syphon a couple of times...

lexus114

Yep,what thomas said. I noticed a difference in the steering doing this.

JimD

You really need to turn the steering wheel with the motor running lock to lock twice, but be careful to just turn until it can't turn anymore, but then immediately start turning back the other way. For reasons I do not understand, if you hold it in the lock position for any period of time it damages the power steering pump. The easiest way to do it in my opinion is to just use a turkey baster every few days and after you have done that 3-4 times you are good to go. Thereafter, just do it everytime you change your oil. I have done this on my son's SC400, my wife's jeep and my BMW 540 and they are all the same.
In case you are wondering why I am here, I signed up for this board when I gave my son his SC400, but I am now thinking of buying my wife a used GX300. However, I have to say that lots of people seem to be having big problems with their tranny and sludge. On the other hand, I guess every vehicle has its problems.

ToyotaLexus

well.... I suctioned all the fluid from the power steering fluid reservoir and filled with Mobil 1 synthetic ATF. Did the process twice.

It's been almost 10 days and the ATF fluid inside the reservoir is just as clear as brand new ATF.... (actually did a comparison by smearing them on a white paper to see if there's any difference) so I guess this is clean enough?