Disposal vibrates excessively and causes the sink or countertop to shake during operation.

Safety first: Turn OFF power to the disposal before inspection.

• Check for debris: Look inside the American Standard disposal and remove any large items or buildup on one side of the grinding plate using tongs.
• Inspect impellers: Use a wooden stick to move the impeller arms. If one is bent or missing, the assembly is imbalanced.
• Verify mounting: From under the sink, check that the mounting ring is fully rotated and locked. Tighten the three mounting screws evenly if your model uses them.
• Check rubber gasket: Ensure the rubber sink mount gasket is seated evenly between the flange and mounting ring.
• Test operation: Run water and briefly operate the unit. If vibration remains severe, the grinding assembly may be damaged and the disposal should be replaced.