power steering/auto trans reservoir

I attempted to check the power steering fluid leve on my 2001 325i after hearing a moaning sound when I turned. I looked but couldn't find a power steering reservoir but did find one up in the fromnt of the engine compartment that reads "ATF". Assumimg that to mean automatic transmission fluid goes in there, I filled that and the moan went away. Is that a common reservoir for both the auto trans fill and power steering on the E46? Thanks.

That really means the power steering is serviced with ATF, Automatic Transmission Fluid.

I am betting you knew that.

Later,

I have to confess I wasn't too sure especially since I'm not seeing where the trans dipstick is. Thought this was some clever change since my last AT dates to when my wife brought her '78 Sunbird into the marriage and this is my first BMW. But thanks for the reply.