what kind of batteries do i need

looks like your truck takes 2 batteries.the duralast gold 850 cca is whats called for on your truck.$114.99 a piece with core.part#65-DLG

As long as you have batteries that can handle 850 cold cranking amps or above, you will be fine. The group size for the battery is Group 65. This is a universal sizing for the batteries. I respect Joel for his suggestion, but for my money, the place to go is either a dealership or parts store selling a Motorcraft battery. The reason - price (should be less than $100 for the best battery...like...$89.95?), the warranty (something crazy like 7 years pro-rata with 3 years free replacement), and most important - the manufacturer. Johnson Controls makes the replacement batteries for Ford (Motorcraft) and is simply the best in the business, hands down. Your part number is BXT-65850. Good luck!