1999 Dodhe RAm 1500. The known major issue on this truck remaining. This belt makes very loud squealing sound. I tried all the things recommended in my other post years ago but nothing helps. The difference is, it now makes noise in hot weather too not only in winter. I believe it comes from the bell on the photo.
I think it is the fan belt? I can’t explain why the noise is worse when I hit the gas pedal. How difficult is it to replace it?
Believe you are pointing to an alternator. Probably time for a new belt and tensioner check. After new belt check how much give it has, when not running of course. .5" max flex in belt when pushed. tensioner next suspect.
What major issue remains?
As far as the serpentine belt: all the components it drives need to be checked to find out if they rotate freely. It makes more noise when accelerating because it is slipping at a higher RPM.
It is either a loose belt or the bearings the pulleys are attached to. Push in the belt before you start the engine and see if it flexes more than @Barkydog suggested. If that isn’t it, let’s hope it is an idler pulley. The mechanic has to remove the serpentine belt to check this. If the belt isn’t new, replace it, since it’s off anyway.