No multi-weights - someone help me understand!

[GreeCguy]

Good morning fellow oilers: I'm confused. On another post I asked about running straight weight oil verses a multi-weight. One of the replies I received said there was no such thing as a "multi-weight." As a born and raised Lutheran, I have to asked, "What does this mean?"

 

[JonS]

I think he meant that there are no synthetic multi-weights. They are basically straight weights that flow extremly well in cold weather. They (most) have no viscosity improvers in them.

 

[TallPaul]

I think its that instead of multi-weight, its multi-grade (although the two are more or less used interchangably). A high end synthetic like Redline, most of which do not have viscosity index improvers, still is classified as a multi-grade because for example, their 10w30 meets the SAE 30 Grade for 100C viscosity and also meets the requirements for a 10w grade which include cold cranking, cold pumping, and a minimum viscosity. Even a straight grade oil, say a dino SAE 30 grade oil may actually also even meet a 20w grade, but just doesn't say it on the bottle because most everybody doesn't care in that case. Really any oil is multi-weight (if weight means viscosity), varying by temperature.

 

[rpn453]

quote:

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Originally posted by TallPaul: I think its that instead of multi-weight, its multi-grade (although the two are more or less used interchangably).

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That's probably it.