oil change

Badger wrote: I have asked that question a few times to people in the lubricants industries "can you mix different grade oils" answer with a sharp intake of breath "Oh no never mix them"

Then ask "why not"

Had a few answers but none were constructive or plausible.

Its all down to the additives they put in not mixing properly

Hi Rich I always thought an "F" was a baby Ferrari any way just 4 cyl in stead of 8

paulsmgf wrote:

Badger wrote: I have asked that question a few times to people in the lubricants industries "can you mix different grade oils" answer with a sharp intake of breath "Oh no never mix them"

Then ask "why not"

Had a few answers but none were constructive or plausible.

Its all down to the additives they put in not mixing properly

If you buy a mineral oil with additives then they must be mixed with the mineral oil; if you add more mineral oil from a different source what would stop the additive mixing?

Common additives like molybdenum disulfide, PTFE, Teflon and anti foaming additives for diesels are all in modern mineral oil these days and they all mix.

We can even buy additives to put in our own mineral oil like STP, Slick 50, ZMax, Wynns, all trying to sell you some story about more MPG or power or something; maybe its true but they all mix.

helsbyman wrote: Hi John
If you read the 1st post I said I have 2lts already plus the system may take 4 1/2 but you only ever get 4 LTS out

Apologies.
The filter would take about half a litre maybe?
I run ours on the upper mark ( not over!) and the old oil doesn't fit in the 4 litre Magnatec container.

Agree with Badger: everyone says don't mix oils but nobody can give a definitive reason.
Our Power Tech division next door to my workplace houses the lubricant research division of EON for all our power plants worldwide. I'll ask, but might not understand the answer: these are some proper Mad Professor types!