Google 5.0 Cummins V8 Toyota and you will find a number of reports that state it will be offered in 2016. I am almost positive I read a formal announcement in the past, but can't find it now. All the articles seem to be from early 2014.
2012 RAM 3500 Laramie Longhorn DRW CC 4x4 Max Tow, Cummins HO, 60 gallon RDS aux fuel tank, Reese 18k Elite hitch
2003 Dodge Ram 3500 QC SB 4x4 Cummins HO NV5600 with Smarty JR, Jacobs EB (sold)
2002 Gulf Stream Sea Hawk 29FRB with Honda EV6010