stop feeding the trolls rotella t6 5w 40 is perfect oil for your tdi. I can show you pics of a motor with 400k on it 10k miles oil changes and not a drop of sludge or build up in the motor and bearings still look good. 5w 40 is a better oil especially in the PD's
I have also run the white bottle non synthetic rottella 15-40 for over 60k in another tdi with no problems.
Run 5w40 over the 5w 30 A cam in a pd car will last much longer if you do.