Not sure how many people do this service but I believe a good figure is that it should be done every 30k miles.
Automatic Transmission Fluid (I use Mobil1 Synthetic) – 1-2 quart(s)
Pliers – 1
Funnel – 1
5/8″ inside diameter clear tubing – 6 feet
Jack – 1
Jack stands – 2
Friend – 1
Rags – Many
1. Jack up the car because it will make things a whole lot easier. Wheels need to be off the ground.
2. Take out as much fluid as possible with an old lotion bottle pump or suck it out somehow with a small tube with your mouth
3. Locate the return line on the power steering reservoir. It should be the one thats closer to the top. If there is fluid above the return line hose (which I do not recommend) place a cup or some sort of container near it so nothing spills.
4. Take off the return line hose and put on a clear tube that fits around it. My clear tube had a 5/8″ inside diameter. It was the same for my 01 corolla and our 96 es300. You’ll need about 5-6 feet of tubing.
5. Run the tubing down as it will make the fluid flow better. Tape it to engine bay somewhere and make sure it doesnt hit any moving parts (pulleys, belts, etc)
6. Now here is where you may need the help of a friend. Have a friend sit inside and turn on the car. Turn the steering wheel lock to lock to pump out all the old fluid. Keep pumping it until most of the fluid is out (it will come out slowly near the end). Now turn off the car and put some fresh fluid inside the reservoir. Make sure you keep your finger on the nipple of the return line on the reservoir so nothing spills out. Put the cap back on, turn on the car, and start pumping out fluid again. Once you see that it all comes out red, that means all the old fluid has been pumped out. You can continue to pump out the rest (like I did) or you can stop here.
7. Put some fluid in the reservoir and keep pumping. Fluid should start to disappear. Keep adding fluid and keep pumping. You will start to hear a whining noise and the steering wheel might start to shake. Dont be alarmed. This is just air in the power steering pump. Keep turning the steering wheel lock to lock to bleed out all the air. Keep adding fluid as it’s necessary. It should be less than a quart.
8. Take it for a spin and see how easy it is to turn now. Check fluid levels again later on.
Links I found useful and you might as well: