Why is there excessive vibration or noise during the wash cycle?

Excessive vibration is commonly caused by an unlevel floor, unremoved shipping bolts, an unbalanced laundry load, or the washer contacting another object. Make sure the washer is installed on a solid, level floor and use the leveling feet to adjust height if needed. Metal objects such as coins, or clothing with metal decorations, can also cause noise during washing, which is considered normal. (Page 18)