Macster

The oil used has nothing to do with the appearance of that "buttery stuff" in the oil filler tube. The buttery stuff shows up if the car is not driven enough to get the oil fully up to temperature and keep it at this temperature long enough to drive the moisture out of the oil.

And both of my car engines have done just fine with 0w-40 oil though I have no problem with anyone using a 5w-40 oil (make that an approved 5w-40 oil) provided the temperature is above -25C. In this extremely low temperature Porsche calls out a 0w-40 oil.

Nor do I have a problem with if the ambient temperatures are mild enough if one wants to run a 5w-50 oil (and again make that an approved 5w-50 oil). As I have mentioned before I have switched over both of my car engines to 5w-50 oil year 'round. It seldom gets below freezing here and on the flip side ambient temperatures can soar over 100F sometimes -- late June 2009 -- reaching 111F. And when I venture out onto the open road when I encounter even 118F ambient temperature I don't give the engine a second thought. I fret about the A/C though and offer silent prayers the A/C continues to work ok. Oh do I pray.

Sneaky Pete

I agree with what Mac says but note there was no mention of 5-30 or 0-30 weights. The only oil that ever gave me butter was M1. Long drives and all. I changed to Syntec and later to DT40 and never saw it again. Just my 2 pennies.

Now about the AC I prayed too.

Sorry to turn this to an oil thread thingy....