bad brakes?

[runnermatt07]

well i did the search but didnt come up with to detailed of anything on it, but basically my brakes are very hard and dont work well, has a whistling noise, used to just on brakeing sometimes, now its constant, (although low) so im assuming its the brake booster, my question now however is how do i take the thing out? i have an 89 325is, please help, i looked at it and see 2 or 3 bolts in the front but no idea how the back comes off,

oooorrr am i off base in thinking that its probably the brake booster, also if not what is it, and finally should i replace any hoses or anything while im at it? thanks!!

[jlevie]

First check to see if the problem is a bad line between the intake and the booster. You can check the booster for leaks with a vacuum pump and gauge.

After removing the master cylinder, the four nuts in the driver's footwell hold the booster in.