I've been told a lot of things regarding this subject but never by someone
like a petro chemist.

Mike

On 9/24/03 10:24 AM, "Matthew" <poll7356@UIDAHO.EDU> wrote:

> I changed oil last night but I had to use oil that was left over from
> other oil changes. It was all new oil but some was 10W-30, some was
> 20W-50, and the other was something else in viscosity. All was the same
> oil mfg...quaker state. Is there any problem with mixing viscosities as
> long as the oil is the same mfg?
>
> -matthew, a chemist at that!
>
>