woah hey, stop knocking on my boy, 94TRDcelica. He's just helpin.
if it is only coming from one side, Check your BREAKS first. Get someone to drive for you thru a parking lot or something, and walk along and look and listen. (the hardest part is letting someone else drive

)
if that is the case, then know that your break pad has a plate between it and the caliper. Get some grease and grease the spot between the plate and the pad, and the plate and the caliper. let it dry and re-test.
That squeak is due to microscopic viberation, the grease will keep it from viberating.
If that dont work, than start looking at your CV's. Directions for that have been posted by 94TRDcelica. However, the squeal would usualy be accompanied by some rough driving...
Now if it isnt indigenous to one side, than check your belts. You can get some belt-desqueeler at your local auto-joint. otherwise, tighten and look for cracks/replace belts.
if none of this works, than install one killer sound system and turn it up untill you dont hear it anymore.

if you cant find the source, than treat the symptoms. Just like a doctor...
This post has been edited by D-Man: Mar 18, 2008 - 8:39 PM