Cordless vacuum makes a loud grinding or rattling noise from the floorhead when the brush bar is engaged.

Safety first: Remove the battery and detach the floorhead before working on the brush bar.

• Remove the brush bar: Flip the floorhead over and release the brush bar via the end cap or latch. Pull it out carefully.
• Clean bearings: Inspect both ends of the brush bar. Remove hair and debris from the bearing areas. Spin the brush bar by hand; it should rotate smoothly. If it feels rough or seized, the bearings are worn.
• Inspect gears (if gear-driven): Remove the bottom plate of the floorhead to access the drive gears. Look for missing teeth or plastic shavings. Replace the gear set or entire floorhead if gears are stripped.
• Check for housing damage: Inspect the inside of the floorhead for cracks or warped plastic that could rub against the brush bar.
• Replace parts as needed: If the brush bar is bent or bearings are worn, replace the brush bar assembly. If internal gears are damaged, replacing the complete motorised floorhead is often the most practical solution.