I guess I answered my own question. I found out that ZTL is a product of Cummins, not Dodge, so it's only on their engines. It's not on any gas engines. However, it's only useful with manual trannies and I don't think anyone makes a gasser with a manual any more.

“In a time of deceit telling the truth is a revolutionary act.”
― George Orwell

It's not over when you lose. It's over when you quit.