Shark PowerDetect Speed cordless vacuum makes a loud, rattling, whistling or grinding noise

The checks in more detail

A rattle suggests something small has been drawn into the floor head or the cup, such as a coin or a button; check the brushroll housing and the airway. A grinding or scraping noise on hard floors is often the brushroll, since hair wound round its ends or a worn bearing rubs, and a stalled brushroll growls. Remove it, cut away the hair, turn it by hand and feel for roughness; a roll that does not turn smoothly needs cleaning or replacing. Check that the cup, the filter cover and the wand are seated, since a loose part rattles. The battery pack can also rattle if it is not clicked in fully.

A motor that screams with a clear path and a clean filter may have worn bearings. Do not run it without the filter. If you smell burning, stop and unplug the charger. Record a short video of the sound for Shark support, who can judge by ear. Use the vacuum on a lower setting when you do not need maximum power, since lower settings are quieter and the PowerDetect system reduces noise on bare floors. Contact Shark with the model number and purchase date if the noise persists after cleaning and checks, since the motor is covered by warranty. The PowerDetect model measures how much dirt is going in and changes the suction automatically,

and on a dusty carpet the motor speeds up and the pitch rises, so you hear this as noise even though nothing is wrong. Lift the cleaner head onto a hard floor and the noise should drop within a few seconds. If the pitch stays high on a bare floor, check the sensor inlet for a blockage, since the system may think it is still on a dirty surface. Look at the dust cup seal, because a seal that is not sealed lets air leak and makes a whistle. The Shark's filters, usually a foam and a felt pair, should be washed monthly and left to dry completely before refitting. Use the Eco setting for light cleaning, which is quieter and uses less battery.