Quick question...This afternoon I had some noise/vibration from the steering wheel so I checked the power steering fluid and it was pretty low. I should prolly bleed the system given that I have no idea when it was done last but it's only about 7 degrees outside...(and I still haven't picked up a heater for the garage ) Is it safe to refill the reservoir without bleeding the old fluid?

Also, an equally paranoid question, will any CHF 7.1 hydraulic fluid do or should I look for a particular brand or get it from BMW?

Thanks,
Dennis