Before the oils changed to be DEF compatible (lower ash when burnt), Shell Rotella was my choice from seeing studies of several scratch/dig tests. Today's Shell Rotella (and other oils) are not the same as the older versions. They know this and they are specking a full synthetic oil for this reason and due to higher operating temperatures.
Sorry Rossn, meant to write DPF not DEF! Duh.Someone please explain to me how DEF, which goes into the Diesel fuel to help it burn cleaner, has anything to do with enigne oils?
Higher operating temps? I bet they're specking a full synthetic to get 10k oil changes from the oil!
Indeed, but as a preventative measure many will go ahead of schedule. As the engine works itself in there is a tendency to have metal shavings floating around. The filter grabs most of them regardless just nice to flush the system.I thought the owners manual said to change the oil every 10,000 miles