Having a mechanic replace the serpentine belt on your Nissan Quest can easily cost over $100. Although this is an important piece, you can easily replace it yourself. Your owner's manual will have most of the instructions on how to replace your belt, but it may not tell you about the nut on the idler pulley.
Jack up the vehicle.
Loosen the nut from the idler pulley. It is located above the oil filter.
Loosen the slackening bolt.
Pull out the belt.
Put the new belt in place and re-tighten the slackening bolt.
