Help! Power steering fluid
 

Today, I checked the power steering fluid reservoir and found that there were only about a bit more than half in it. Is it normal? Should I top it up to full level? What kind of fluid should I use? Recently, there has been some sound when I turn steering wheel during driving, is it something to do with the fluid leaking or less-than-normal fluid in the reservior? Dealer told me that I need to replace the whole steering gear/rack to fix the sound problem. I doubt it. Maybe it is caused by leaking pipe of power steering or maybe it is caused by leaking steering pump? Please give me some advice. Thanks for help.

top it up and see if the noise goes away. i bet it will.
then you'll have to find the source of the leak. i had a leaking hose once. very likely you do too since they tend to fail.

I don't think you're supposed to completely filled the power steering reservoir. You should only fill it up to 80%-85%, at most. This is what's indicated on my other cars. The X's reservoir doesn't have such indication, unfortunately. But if you still have over half of the reservoir filled, then it's not leaking from the system.

The cap has a dipstick
 

Use the dipstick on the power steering resevoir just like you would use the dipstick for engine oil. if i recall correctly, measurement should be done on a cold engine.

There is no dipstick for the power steering resevoir (unless mine is missing one?). As a matter of fact, I don't recall ever seeing one on any of the cars I have owned. Most car's use a somewhat transparent plastic reservoir with level indicators marked on the outside, just like the brake fluid reservoir. But the Bimmer use the non-transparent plastic and with no level indicator at all.

The dipstick is ON the cap. There is a line indicator on it.
Hope this helps..

This happened to mine also. If you top it off the noise will stop. The source of my leak was a power steering line(hose).

Yesterday, I topped up with Shell ATF oil to about 90% full of the revervoir, and found that the sound still there but much improved which means much less than before. I checked the oil level after about 50 KM driving, and found the oil level kept about 90% full which means no leakage (or maybe it is leaking very very slowly, I may check one week later). Any idea?

Man...did I get gipped by BMW on the power steering fluid measuring stick? I don't have one on my '04 3.0i :rofl:

Hi Roger -

Do a search under my posts or search for moaning and groaning ........
Different PS fluids have slightly different viscosities.

In my case, I experimented with a couple till I found one that was just right.....Mobil 1.