AAR mechanical designations
I don't know if the anwser to Mark Mathau's question is here, but this
is a useful link to bookmark for reference.
Eric Neubauer's home page
He says that "TW" designates a "[t]ank car with a wooden tank used
for vinegar, pickled produce, etc." Does this disqualify a car with
TWO wooden tanks? And what is included under "etc." ? Your guess is as
good as mine.
CNJ on one side, LV and RDG on the other