The first # refers to the base weight of the oil. That is the weight it is
always. It has additives that make it perform like a 30 weight.A 10w30 is a
10 weight always,but performs like a 30 weight. If you want a straight
weight oil you would buy a 30w only.Which would be a thickerbased oil. I
have always heard of 5 weight oils. And I have seen the ones rated 0w
something,but always have wondered how you would have a zero weight oil.I
asked our distributor about this.He has a hard time also with this. He
thought that it must be at somewhere under 5 so that they could call it a
0w. Afterall wouldn't a zero weight be air or at least the viscosity of
diesel fuel. Also I asked him about how the newer cars are calling for
lighter oils in the crankcase. He says that it has to do with gas mileage of
the vehicles.You will get better gas mileage with a lighter based oil. I
perfer better protection then better gas mileage results. Stick with good
oil and you can't go far wrong.Just my two cents. Thanks
Malcom
"Stephen Bigelow" <sbigelowPOV@rogers.com> wrote in message
news:uIy2b.29040$_V.25170@news04.bloor.is.net.cabl e.rogers.com...
>
> "Bonnevilles R Kewl" <spam@b.gone> wrote in message
> news:MPG.19b46a03efb7747f9897b0@news-server.woh.rr.com...
> > > > Technically, The difference is what weight you use. If your V-8
runs
> on
> > > > 20w50, and you decide to put in 5W50. You'll definitely see an
> > > improvement,
> > > > dino or synthetic.
> > >
> > > Really.
> > >
> > > Why would that be?
> >
> > W does not equal weight, it stands for winter. The point he was trying
> > to make that the thinner the oil the less it slugs down the engine.
> > (0w30 is thinner than 10w30.)
>
> Really.
>
> And all this time, I thought 30=30!
>
>