thanks for your reply SNS3Guppy
Sorry for not mentioning the a/c type, I'm talking about Boeing 737-800.
From your answer I understood that an out of limit fuel imbalance could cause the wing/tank that has the low fuel might bend. However I am still not sure if this will happen with the center tank fuel is empty. (in the 737 we use fuel from the center tank fuel first untill it becomes zero). Also I still do not understand how this could affect the landing gear?