started 1 week ago but since 2day it has become constant as soon as i start car all the way through driving also until i shut car off... when i have my foot on pedal driving it gets extremely loud..i even put wd-40 on the alternator belt an it stopped for about 2 minutes ..(i guess the spray wore off)the it came back loud *** hell. i even noticed the power a lil sluggish...any other suggestions...all info appreciated.,..thanx..i am guessing i need a new alternator belt...so i will buy one tomorrow morning.

It could be the alternator bearing if so you will have to replace the alternator but you could try the belt first cheaper way to start out if it not that and its the alternator then you will have new belt and alt. when you take the belt of see if the alt. spins freely if not probably the bearings in alt.

if in fact it was the bearing..why would it stop when i only put wd-40 on the belt that spins on the alternator pulley(stopping for about 2 minutes an coming back on)?

i have the same problem..i'm just assuming it's one of the belts so i'm going to change it out.

Try this out: Take something long (like a long-handled screwdriver) and start up the car, then place the long item on the alt. If you can hear excess noise, it's the bearing. I had this happen to me and that's what my service adviser at the dealer did to check it out.

woah stop right there....WD40 is a lubricant! It will only make the squealing worse in the long run. You want to get some "belt dressing" at the local auto parts store. Do NOT spray WD40 on belts, ever. Also check belt deflection, it may be loose (there is a tensioner).

That said, now that the belt is doused in lubricant (WD40), you probably should replace it anyhow...

Replacing the belt would be the first step. Might have gotten wet somehow and slipped, glazing the belt and requiring replacement.

You have to tight this...

ok...thanx all for info.....this site is a big help.....im now going to get the belt..updates in a few