GRSEARS92

I have a 92 prelude Si automatic w/ 200,000+ miles. Bought it used from a little old lady (my mother) who took very good care of it. I've owned it for 3-4 years now and it's been pretty much trouble free up until now. After i start it and warm it up when I put it in reverse i get a noise that almost sounds like a pump whining or something similar to that. The faster I go the louder it gets but when I apply the brakes it quiets down some. Just to let you know the ABS hasen't worked in 10+ years so it's been working like regular power brakes. When I shift into drive it seems to pretty much go away or it's very faint. I checked the brake pads and they're a bit worn but nothing to extreme. hope someone can help.