Had to have the daughter's Taurus towed last night. While the guy was writing out the bill, I was looking at the door. There were two stickers on it. One was surely written by Captain Obvious. RIDING CLUTCH WILL CAUSE PREMATURE WEAR.
The other one was the about the indications and procedure to "regenerate" the particulate filter system. I can't recall all the details but it required some switch to be thrown, and then leaving the vehicle sit (presumed running) for up to 20 minutes until it indicates that the regen cycle is complete.
I thought that there was something very wrong with this picture in seeking to clean things up.
I would have a look at RTS 5W40 or M1 0W40 both are good oils. If I knew where "a prison island" was and what their average weather is like I might even go with a 15W40 if it warm during the oil change interval or warm year round!
Castrol Edge is not not recommended for that engine going byt he lube tool on castrols website. the use SLX professional III and mentions VW 507 spec. yes it's dear but i would only put the best in a diesel .