In my 99 durango cna i swap my 44re to a 46re with no issues ? essentially looking for an upgrade but also "Plug and Play" basically

 

Yes you can.. the 46RE is basically a beefed up 44RE.

IMHO, unless you are planning on doing alot of heavy towing there really is not a benefit to the swap except having a fresh transmission (assuming your rebuild it before throwing it in).