Disputing billable weight charges from Fedex

[dabur-263]

Hello, can anyone tell me how to go about putting in a claim on bogus billable weight charges from FedEx ? The package was 5lbs but FedEx billed me for 13lbs ( $35.71 )

[disneyshopper]

What were the dimensions of the package?  It's possible that Fed Ex is billing for dimensional weight instead of actual weight if the package is greater than 1728 cubic inches.