Yes
Yes
synthetic to conventional - ok conventional to synthetic - no
It can be. The 5w20 is the weight of the oil which you can buy conventional or synthetic. If it is synthetic it will say so right on the container. If it does not say synthetic it is conventional oil.
Yes, you can even mix synthetic with conventional oil.
Synthetic and conventional oil can be mixed and used with no problem. That is exactly what a synthetic blend that you can buy is. A mix of synthetic oil and conventional.
It is conventional oil and contains no synthetic oil. 3000 & 5000 are part synthetic and part conventional. 7000 is a full synthetic oil.
You can blend synthetic ATF with conventional ATF.
9.5 quarts.15w40 conventional or 5w40 synthetic.9.5 quarts.15w40 conventional or 5w40 synthetic.
You can use synthetic, synthetic blend, or conventional oil. It is your choice.
That's easy synthetic oil. Ill tell you why it sounds better
It is a combination of synthetic oil and conventional oil.
The engine uses 5W30. It can be synthetic or conventional.The engine uses 5W30. It can be synthetic or conventional.