How Do i Stop The Squeeking Noise under my Frontera?

The car has started squeeking really loud from underneath,i have sprayed all under the front end(where the noise seem's to be coming from)like a mechanic told me to with brake fluid,blathered all under the front end,but it is just as loud,anyone else ever had this problem,and has any idea how to stop it ? PLEASE Help,thank you from dave