[arcosine]

.Ive run 0-w20 for 75 k miles, no ill effects.

I have a question, when does the majority of engine wear occur?

Start up.

Which oil reaches the bearings first, a thick oil or a thin oil? Well of course the oil that flows easiest. There is an pressure regulator, so when cold both oils have the same pressure. I took the regulator out of my moms 75 le mans, because it broke, and the oil filter puffed up.

My Saturn engine is designed for 100 hp at 5000 rpm, I rarely go over 3000, usually its under 2000. Like I said 75k no ill effects. I can lug it under 1000 rpm and no oil light comes on.

The Saturn will rust through before the engine wears out.


In the early 80s's I had a 68 beetle. I put a teflon oil treatment in the engine. I had to turn down the idle afterward. Is the Saturn idling faster now? Maybe, its hard to tell, but does seem faster. I have the aux air port mostly plugged.

If I had an escort with 500k id probably use 10w40 too, especially if it knocked with thinner oil. I use to use 10w-40, then 5-w30. I started 0-w20 when I first saw in at Walmart, about 20 years ago. Diesels need thicker oil, I use 0w40 in my TDI.