2005 Chrysler Pacifica 3.8

Hi I have a 05 Chrysler Pacifica 3.8 without
warning my car started to lose power I can't get it
to highway speeds and it's making a noise high
pitched from the front of my car and also when I
press the gas it doesn't seem to have the power to
go over 10 miles also can't get it to excelerate
enough speed to make it up small hills it starts to
lose more speed can anyone tell me what the
problem is my mechanic nor myself can figure this
out and I've put so much money into it already