Synthetic oil is synthetic oil. Any major brand will be of high quality.
castrol extra 20W50
Magnetec 10w-40 should be the best oil
In a 1997 N15 Pulsar with the GA15DE engine, I use a 10w40 synthetic oil (Castrol Magnatec) recommended by the local store. To find the right oil you can go to: http://www.datateck.com.au/lube/castr_nz/default.asp Just enter info on your car and it will say what oil is recommended.
The best synthetic oil for your car is by far Penzoil full synthetic. Penzoil's propitiatory blend of oil provides the best lubrication for your engine, ensuring that no friction occurs between engine parts, which can lead to costly repairs.
The best oil for a Land Rover is usually a synthetic oil like Valvoline.
10w30 synthetic
7 QUARTS OF SYNTHETIC OIL.
It is always best to use the oil recommended by your vehicle manufacture. If you are considering the difference between Synthetic oil and Conventional (pumped from the ground); if your owner's manual says to use synthetic, you need to use synthetic. But if your engine was designed around conventional, then you can upgrade to synthetic. Synthetic has advantages as being better at cleaning and protection your engine, but if you have a higher mileage vehicle, synthetic can cause leakage of the gaskets and oil seals.
Amsoil is considered the best synthetic oil by some individuals. Mobil and Shell also provide great quality synthetic oils. These products are not considered suitable for use on hair.
You can mix part synthetic oil with full synthetic oil.
Amsoil By far the best.
Semi synthetic or synthetic blend is a combination of synthetic and conventional oil. Full synthetic oil is just that 100% synthetic oil.