Why heat up multi-weight oil before changing?

[Travelor]

Thanks, Now this makes sense.

That chart is very revealing as to why to use multi-weight. Is the 15W-40 chart example for Rotella T6?

I like the idea of pouring some clean oil in to clean out the bottom. Seems like I always have a little oil left over from various changes. The cans just sits there just waiting for something! Now I know how to put the left overs to good use.

I remember in the "old days" you could buy flush oil or sometimes just run coal oil for a few minutes to flush out the engine and sump. That was when everything was single weight dino. Sort'a makes me sound like a dino!

Thanks again

Wow!! "Coal Oil". Haven't heard that phrase in a very long time. My grandfather was a machinist/tool & die maker and swore by coal oil as an antiseptic and healing aid for cuts and gouges. I tried it myself several times and it seemed like it really did speed up the healing. Of course, modern doctors don't have a clue about it.