To find the right size battery for a vehicle, use an online service, such as Wal-Mart's battery finder or Auto Zone's vehicle selection tool. Required information includes year, make, model and engine size of the vehicle for both tools. When the user enters this information, he receives the battery size.
Another way to find the appropriate battery size for a vehicle is to know the battery's BCI number, which is the Battery Council International number. When the correct size matches, other necessary specifications for finding the right battery include cranking amps, cold cranking amps, amp hours and reserve capacity ratings.