Loud noises coming from your garbage disposal mean an obstruction is jamming the blades. This is a common issue, and the obstruction is usually a piece of cutlery or hard-to-cut food item, such as meat bones. You can sometimes remove the item by hand, but if not, you will need to get under the sink to fix the jam.
Turn the garbage disposal off and wait two minutes to ensure the blades are no longer spinning. Unplug the disposal under the sink.
Move the rubber coverings of the disposal to the side with your hand and shine a flashlight beam into the disposal unit. See if the obstruction is plainly visible. Look for forks, measuring spoons or large pieces of food or metal. If you see the problem, reach in and pull out the obstruction.
Plug the disposal back in. Turn the water on and turn on the disposal. If the noise is gone, you have solved the problem. If the noise is still present, there is still a jam you cannot see.
Unplug the disposal again. Insert a hex-head Allen wrench into the small hole on the bottom of the disposal. Turn the wrench counterclockwise and then clockwise until you feel the resistance from the obstruction. Work the wrench back and forth until the obstruction comes free and you can spin the wrench all the way around.
Insert a garbage disposal wrench into the top of the disposal from the opening in the sink, if the Allen wrench could not free the obstruction. Slowly turn the wrench until it firmly grips the blade wheel.
Push the wrench counterclockwise, then clockwise. Use as much force as necessary to clear the obstruction. Repeat the turning motion until the blades spin freely, indicating the obstruction is gone. Plug the disposal back in.