Join Date: Aug 2010
Location: 2013 Cross Country
It's an interesting idea, but it depends on what the new speedo is looking for, to make it happy. It now displays trouble codes, which suggests there may be some sort of bus (CAN Bus?) connection to the ECM, which just wasn't there previously.
I went looking for a wiring diagram for a 2011 or newer to see what the connections are, but so far, no luck.