Pulleys that guide and support accessory belts.
These pulleys support the serpentine or V-belt as it moves around the front of the engine. Wear can cause whine, chirp or grinding noises. Match pulley diameter and width and confirm belt type. Replace worn belts and inspect the tensioner while servicing pulleys. Correct pulley bearings reduce belt noise and help avoid sudden failure.
Worn bearings, belt misalignment or tensioner issues.
Replace cracked or glazed belts when servicing pulleys.
Modern pulley bearings are sealed and do not need extra grease.