richardh10
Well-Known Member
Is there any reason not to mix different brands of engine oil? Obviously the same SAE etc, just a different make.
Mixing oils
- Thread starter richardh10
- Start date
ChromeDome
Well-Known Member
If same classification and equally meeting or exceeding the engine manufacturer requirement specification, I see no reason not mix them.
If any doubt at all, the answer is no, get fresh oil. Oil and filter after all is so much cheaper than engine repair.
If any doubt at all, the answer is no, get fresh oil. Oil and filter after all is so much cheaper than engine repair.
Refueler
Well-Known Member
No problem as long as specs are similar.
But I would suggest you do not mix in cheap recycled oil .....
And I would suggest that you do not mix synthetic and non-synthetic ....
But I would suggest you do not mix in cheap recycled oil .....
And I would suggest that you do not mix synthetic and non-synthetic ....
vyv_cox
Well-Known Member
Although all major company oils will comply with relevant specifications they may not use the same additive packages. They will not react, as this is a requirement, but the additives may be diluted. Probably not a problem in a low power engine such as yacht auxiliaries
Refueler
Well-Known Member
Actually there are very few producers of additives and near all use same or similar component production. A company such as Baker Hughes will be supplying large majority of the industry and other smaller Lub Oil Co's will most likely be buying from intermediarys who are buying from such as Baker Hughes.
For over 10 years I ran such supplies for various clients in EU and UK. The label may be different - but the Additive was same.
The problem comes when Lub has other additives when recycled and then introduced to 'virgin' base. The 'rejuvenation' additives can be specific to a requirement - then have problem with the other base its mixed with. Its why I posted to suggest not to mix recycled oil into your sump. Use all or nothing. If you use all recycled - then I suggest do not run over oil change recc'd time.
vyv_cox
Well-Known Member
Not sure who you were supplying but the majors definitely do not use the same additives or suppliers.
thinwater
Well-Known Member
That is my experience.
In general, oil and engine coolant manufactures have learned that if their product is not highly compatable with other products, any bad reactions will be blamed on them (early Dexcool comes to mind). Though intentional mixing is not common (but not that rare either), low ratio mixing during oil or coolant changes happens as often as not.
vyv_cox
Well-Known Member
Many specifications call for compatibility at 10:90, 50:50 and 90:10 with similar products but this does not mean that the additives will actually contribute.
Refueler
Well-Known Member
Our work was with all Majors ..... and small co's.
Baker Hughes is the worlds supplier ..........
Our work covered from Base Oil shipments for major contracts - through to blend stocks and additives .....
What do I know ?? I only supplied and worked with the stuff ...
vyv_cox
Well-Known Member
Shell has its own additives company and a research group. I don't deny that they may buy in some additives but their base number control, probably the major component after base oil, is unique.
R.Ems
Well-Known Member
Not to argue with your expertise, but I have gained the, maybe wrong, impression that the very popular 'semi-synthetic' engine oils are a mixture already?
vyv_cox
Well-Known Member
Semi synthetic oils are distilled varieties (Group 3) that have most of the properties of a full synthetic.
Refueler
Well-Known Member
I cannot see where I mentioned Semi Synthetic .....
I repeat - it is not wise to mix Synthetic and Non-Synthetic .............. mixing the two is not same as Semi out of the can.
Refueler
Well-Known Member
thinwater
Well-Known Member
^^ This.
coopec
N/A
As an Internal Auditor for Caltex oil I once watched them blending motor oils for Calten (as well as an opposition oil company) in an underfloor, super-hot mixing machine.
I don't remember all the additive names but they both had a "base stock", a dye and Lubrizol.
Caltex Oil had 9 ingredients and the opposition 5.
Here is an interesting article on the subject.
What Is Motor Oil?
I don't remember all the additive names but they both had a "base stock", a dye and Lubrizol.
Caltex Oil had 9 ingredients and the opposition 5.
Here is an interesting article on the subject.
What Is Motor Oil?
Other threads that may be of interest
