Just a little service work today and a "how to" on the power steering system.
My methods for service sometimes differ from others so as usual, I present my method - use it or discard it :biggrin2: Either way, it works for me
In both my 4runners, I had not worked over the power steering fluid at all. In my previous cars, my method was as follows:
Step 1: Use a service syringe to remove all fluid from the PS tank. I find I can remove between 140 - 200mL of fluid. Just depends on the angle you can get the tube into the tank
Step 2: Once the fluid is removed, Re-fill the exact amount you extracted with new
Step 3: Start the car and turn the wheel lock to lock 3 times
Step 4: Repeat the extraction / fill process 3-5 times if the system has never been serviced. The system does not hold much, so at best, have 2 quarts on standby
Step 5: Do an extraction and fill every other oil change. This will keep the PS fluid in outstanding condition without mess for the life of the car / rack and PS system
Some will say a full flush every 60-100K miles is the only way to go. I disagree unless you flush, and then go off regular interval partial drain and fills. With the PS system, a lot of build up and grime happens especially when it has been neglected as many of ours 2nd, 3rd, 4th+ hand cars are. You can do a full flush and the fluid may look really good! Give it a few hundred miles and it will look like crap again as the detergents and such in the new fluid break down the crap and it is released back into the system.
That is why I feel a constant cycle of changes is best for systems like power steering and even transmission fluid / systems with high mileage intervals.
Some will come back with the argument "you do not change your oil 1 quart at a time do you?" Not at all. That is because it is a frequent service item. If I did change 1 quart every 1000 miles for example, I can assure you, my oil would be in just as good of condition, if not better than oil changed every 5K miles. In this, the solution to pollution, is dilution. PS systems are usually not serviced for 100K miles (or way more lol), same with transmissions. However a drain and fill on either at regular intervals, keeps the overall fluid condition in top notch shape / measurably - continuously vs fluid that is GREAT! degrading... degrading... pretty bad... terrible fluid... change it... and start the LONG cycle over.
Some pics of todays service work on my white 4runner. I also did my silver but did not take pics. Does not look like anyone has touched the PS system since new in the white gunner (does not surprise me). Shame on me for not jumping on it right away when I picked it up, but other goodies had priority.
This particular service took about 25 minutes and did not spill a drop of fluid and required hardly any effort. The fluid was BLACK, nearly like burnt motor oil. So this took 5 drain and fills / starting the 4runner and turning lock to lock 3 times in between each one to get it to the condition it is in now.
As I previously mentioned, I will now extract / fill every other oil change (10K miles) and it will remain in excellent condition and actually get better over time. I only found my 60mL syringe so this process actually takes about 10 minutes if you have a 200mL syringe (they sell them online as brake - oil inspection syringes)
Before: Notice the nastyness on the tip of the syringe tube. Gunk that stirred up from inside the PS tank. I am tempted to use a magnafine filter on the PS for 30K miles or so until I clear the sediment up and the detergents in the new fluid break down the grime. Will see how it looks in 10K miles. If you have this gunk on the tube, make sure you wipe the tube clean before putting it into new fluid to suck up fresh ATF.
After the process. Not flawless but in 2 changes or so, she will be as good as new. And with continuous small changes, she will remain as new.
And just for comparison, brand new ATF