This thread contains IH construction equipment serial number lists and engine cross reference information. Excellent info for ascertaining the year of manufacture of your crawler tractor and the engine it uses, not to mention the other machines that use the same engine.
If you have questions about your machine, post them as new topics. If you have additional info pertaining to this topic, please feel free to add it.
Starting this off with this web site link to a set of very nice serial number