DIAGNOSIS A high-pitched noise from the floor nozzle indicates friction on the brushroll. The most common cause is a worn or damaged drive belt.
FIX Replace the brushroll drive belt. 1. Unplug the vacuum. 2. Flip the floor nozzle. 3. Use a coin to turn the two locks, remove the cover, and lift out the brushroll. 4. Slide the old belt off the motor shaft and brushroll end. 5. Install the new Shark-recommended belt (model SV1106 or equivalent). Reassemble.
IF THAT DIDN'T WORK Inspect the brushroll bearings at each end. If the brushroll does not spin freely by hand, or if the ends are melted/deformed, the brushroll assembly must be replaced.
HEADS UP Do not run the vacuum with this noise. Continued use with a failing belt or seized bearing can damage the motor in the floor nozzle.