I wouldn't worry too much about heavy oil. I would just start making sure you're getting the correct oil in there. Remember, 5w30 or 0w40 Synthetic ONLY is what you need too make sure you're not having sludge in there. To be safe, anything that says european blend and with those weights is what you should use for awhile.I have a 2000 turbo with a little bit of a rattle. I would like to put some heavy oil in it. What is the heaviest oil I can put in this car?
It has 150,000 miles on it.