awd problems
 

ok, i normally dont use my awd/4h/4l but recently switched it on to find nothing happen, i was told this could be the result of a stuck solenoid, and that it could most likely be freedwith a little light persuasion from a hammer on the outer casing. i tried thiswith no result. im worried it may be something a little worse, i normally listen to music in the car but lately have been going without, and have also noted a harmonic ringing/whine from the rear end on acceleration, very seldom i can get the car to engage awd but not 4l or 4h, with awd engaged the car seems to stumble a bit and stutter, but in 2wd this is not the case, although the ringing persists. any ideas on any of this? the car is a 97 5.4 eddie bauer with all options.