Mixed different brands of oil

[imperialv]

hi guys,

i have several 1/2 liters of unused oil... Can I mixed this in my next oil change. Both unused oil have the same rating but different brand.


Would this be bad?

[niky]

As long as they both meet the requirements for your engine (API number and weight), there's no problem. Just note that if one is synthetic and the other is mineral or semi-synthetic, you should follow the change interval for the mineral one, as that will break down sooner. And since synthetics are built on a mineral base, anyway, you're not violating some natural law by mixing the two...

[joseph luntok]

Rule of thumb: All Oils are not the same.
However, if the API and Viscosity grades are all the same, then even if it is of different brands, it is miscible. It can be mixed and will not cause any damage to the engine. Make sure your remaining oils are not contaminated with any foreign materials.
Now, if your oils are of different characteristics, can it be mixed and used without harming the engine? In many instances yes, It might have a change in the performance but it wont cause damage nor any major significant adverse effect on the engine. Just shorten drain interval. However, if you are not sure or does not have indepth understanding about lubrication, consult a professional with lubrication knowledge.
I would recommend to use one type of oil (API, Viscosity/grade, mineral or synthetic based) for simplification and also for steady performance of the engine. Check your owners manual.