If your LG stacked washer and dryer vibrate at start up, confirm that the leveling feet are properly installed on the bottom of the component system. If the leveling feet were never installed, review your owner's manual for the installation instructions. The feet can be adjusted by loosening or tightening a bolt to make each foot longer or shorter.
If your LG stacked washer and dryer unit is new, verify that all of the shipping materials were removed prior to use. One rod left underneath the washer or Styrofoam block between the two appliances can affect the entire unit’s balance, resulting in vibration at the start and sometimes throughout each washing and drying cycle, depending on where the materials are located. Thoroughly inspect the washer and dryer for shipping materials and get rid of any that remain. Once all materials are removed, your stacked washer and dryer shouldn’t vibrate.
Review the operating instructions that came with your LG stacked washer and dryer. The instructions will provide information on how to fill the washer and dryer to prevent you from overloading each appliance with laundry, which can impact the unit’s stability. For example, if you overload the washing machine, it might vibrate during the entire washing cycle, especially from the start as the washer’s balancing mechanism struggles to adjust to a heavy drum. Remove a couple of items if the washer starts to vibrate then restart the cycle.
Verify that your LG stacked washer and dryer unit is stacked correctly. If the dryer isn’t secure on top of the washer, review the manual for installation instructions and make the necessary adjustment. If you can rock the dryer from side to side, then the unit will likely vibrate each time one of the appliances is started. Contact LG if you encounter problems with the installation. A technician can come to your home and assist you in stacking the washer and dryer so that it’s done properly and vibration doesn’t occur.