Re: Lonnnng Time since I replaced any Serpentine belt!
1st, I prefer Motorcraft belts.
2nd, if the tensioner is worn (usually will be kicked out at an angle) or feels like it wants to stick and doesn't want to move freely...I'd replace it at the same time. Also check idler pulley for noise or wear, especially if it's made of plastic.
2008 Vista Blue Ranger XLT