Absolutely not. Ignore anyone who tells you different.
That's okay.
No, you can even mix synthetic with conventional oil. It will do no harm at all.
Yes but once you do there is no turning back and no mixing regular motor oil ever again with the synthetic oil....only straight synthetic....or use semi synthetic....now that can be mixed with regular motor oil in a pinch.
The best motor oil for you car depends on the car. Many old cars can only handle regular motor oil.
motor oil, of any kind, would kill most plants
Synthetic oil or a blend of Synthetic and regular oil is much better for your vehicle than regular oil alone. Synthetic oil is MUCH more expenshive. If you change your regular oil every 3 months or 3,000 miles I will be fine.
are you sure you are looking at engine oil or is it the tranny fluid(which is reddish brown but there are also synthetic motor oil that are reddish in color but DO NOT MIX regular oil w/synthetic oil make sure of what you have before adding causes major engine problems
All regular harley's take 20w50 motor oil, regular or synthetic is your choice.
5w-30 is recommended and you can use either regular oil or synthetic.
Nothing happens, they just mix. You can buy "blended" motor oil.
No. It will ruin an engine. The above answer is 100% wrong. You can mix convention oil with synthetic and it will do no harm at all. When you see them selling Synthetic blend that is what you are buying. A blend of synthetic and conventional oil.
20/50 SYNTHETIC OR REGULAR MOTOR OIL............ CHUCK MC