In an 01, it's about time I think, that is if it is the original. When I do mine I do the idler pulley as well, about a $20 part from the dealer.
Get new belt, idler pulley, Krikitt II serpentine belt gauge from napa, ~$14.
Remove the electric fan to make life easier, unplug, unbolt and lift it out.
Loosen the idler pulley center bolt about 2 or 3 turns.
Start turning the bolt adjuster out till the belt frees up and can be removed.
Remove the center bolt on the idler pulley and remove that.
Replace the idler pulley and allow enough loosenes to allow it to adjust.
Route and install the new belt.
Tighten the adjuster up and stick the belt tension gauge on it, adjust to 190lbs for a new belt, 160lbs for a used belt, new belt=one run for less than 15 minutes, used belt is one run for more than 15 minutes.
Tighten the idler center bolt back down
Reinstall the electric fan and plug it back in.
The fan connector has TWO locks on it so be aware of that and don't force it apart or you will break it.
I broke down and bought a special wrench that is used for serpentine belt removal and installation, it's LONG box type wrench with 4 different ends on it, one of them fits the idler bolt. Most mechanics tool companies make them just for this...
cracks across the belt tracks are kind of normal, it's the long ones you have to look out for..
