That's what I have, an 06 srw dodge ram 3500 Cummins, ordered it new from factoryFor some of you skeptics on Shell Rotella T6......I use it in my 08 Toyota Matrix since new......it now has 170,xxx miles...runs like a champ.
I used it in my 2012 R6 which I bought new....This was a daily driver and a track bike...yes, I used this oil in my track bike that saw 14k rpm shift points continuously.....for entire track days which equates to about 5-7 sessions....each session being 10-15 minutes long.
I also use it for my dads 03 3500 Cummins RAM.
I will now use it for my Viking. Great stuff, cheap, and versatile. What more can you ask for?