Full taper spring stamping numbers can most commonly be found on the end of the first leaf. Other locations include the side, bottom or top of the clip, or at the end of the wrapper.
Multileaf springs stamping numbers can most commonly be found on the side, top or bottom of the clip. They may also be found on the bottom of the last leaf beside the center bolt or on the end of the shortest leaf.
Trailer leaf spring stamping numbers are found on the outside of the hook.
In many cases, the stamping number may contain only a part of the O.E.M. part number. Ford usually only stamps the prefix and the suffix. The base must be added to complete the part number. For example F3HT5310JA, D7HT5560AUA or D1TA5588AA, whereas 5310 represents a front spring position, 5560 a rear position and 5588 a helper spring.