CTCI Authenticity Chairman
A frequently ask question is what type and where can I buy a battery for my Thunderbird. It is usually very simple to buy a correct battery in most any town that has a Interstate Battery Dealer.
The original type battery for a 1955 model is a 6V battery that is approximately 5.5″ wide,10′ long and 8′ tall. The Interstate part number is SRM-2.
The 1956 and 1957 model uses a 12V battery that is approximately 5.5″ wide,12,5″ long and 8′ deep. The Interstate Battery part number is 29NF-VHD.
These batteries are still widely used in commercial and farm equipment.
They are also available from NAPA Auto part stores and Allstate (Sears).