Originally Posted by lectraglidedad
How do you tell the date part of these numbers. I know that the part number for seal rebuilds are the same that's why I'm thinking they might work.
A Harley part number is a five digit number prefix followed by a dash "-" and then a two digit number suffix. (Exception being fasteners)
The five digit number refers to a particular part. The two digit number refers to the year it went into service. (Some exceptions being a letter that follows the two digit number indicating a minor change)
For example: The SLIDER TUBE on the front fork of my 2005 FXDI has a part number of 45395-92. The "45395" refers to a slider tube and the "92" refers to the fact it was first placed into service in 1992.
Hence any FXD slider tube from 1992-2005 is the same.
By looking at the two digit suffix for your bike you can see when a particular part went into service.
You can tell if something WILL work - the part numbers are the same. You CANNOT tell if something WON'T work - the part may still fit/function even it it isn't the current part.