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Is power steering flush necessary?

In both Flex A and Flex B services the fluid levels are checked and corrected, is it still even necessary? My car just hit 30k miles without it.

Oh wow, how often do you typically do it? Manual says every 20k but I'm at 30k without any issues. Dealer is charging $110.

I just did this last weekend. With a suction pump and bottle (about $10) or a turkey baster with a longer suction hose, I can suck 1/4 liter out of the reservoir each time. It won't do all of the fluid, but after 1 liter exchanged mine is about 1/4th as brown as it was before and I have a second liter to do it again in a couple of weeks. A liter of fluid was around $8.25 on PartsGeek, so around $25 with shipping, plus the $10 for the fluid sucker and you are done in about 15-20 minutes, tops.

It really is just about the easiest job you can do on the whole engine. It really will take longer just to drive to the dealer, not to mention giving them $100+.

Quote:

Originally Posted by ForcedInduction (Post 161415)

Replacing the reservoir fluid is not enough, it only holds 1/5 the system capacity.
Remove the return line and put it in a 1gallon bottle, lift the front wheels off the ground, turn the wheels side to side and replace the fluid as it empties out.

Granted, it's not ideal. But the total system capacity is only 1 liter and even if I change only 1/4 of that each time (a long tube to suck with really helps over the turkey baster, you gotta squeeze down into the bottom of the reservoir), then crank the wheel while running it, stop to stop 4 or 5 times between changes, it really lightened up the fluid. And Ill do it again. Putting 2 liters in that way should change nearly all of it.

Look at it this way: .75^4 leaves 31.6% of the old fluid in there. .75^8 (two liter changeover) leaves 10% of the old fluid in there and the total cost is $17 for fluid, no disconnected hoses and no chances of air in the system or running the pump dry, which is very bad for hydraulic pumps, causing shock pressures to exist as it tries to pump the air out. That's why when you do drain it you have to "bump start" it a couple of times, running for only a second or two each time to push the air out without building up the 1500psi that can actually compress the air so much it gets very hot.

So, if you want to spend an hour or more and get ALL of the fluid and take all of the precautions of running a dry pump, go ahead. It's the "right" way to do it. But I just throw two liters at it and call it done.