Ok, I used to have it all figured out, but then I stumbled on this webpage, and now I am really confused. I recently purchased a 99 VW passat with the 1.8T motor, with 55K miles. The dealership had changed the oil to penzoil 5W-30. After I bought it, I immediately changed it to Mobil 1 10W-30, as that is what I use in my V-10 Dodge. However, now I am considering switching to the Mobil 1 0w-40, based on what I picked up here. My question is, am I safe to run the 10W-30 out to 5000 miles before changing, or should I dump it now, with about 1500 miles on it? I am concerned about the heat capacity of the 30W vs the 40W in regards to the turbo engine. It does get hot here, over 100 at times. I just completed a 1000 mile trip with the average ambient at 85-90 F, with the 10W-30, and didn't use any. Speeds averaged around 80 mph, with bursts to 100 mph.
Any opinions?
Tom
Any opinions?
Tom