Section. I bought a 3 pack of Mag1 5 quart bottles (15 qts) for $62 on Amazon shipped free. This is what I asked.....Could you tell me the difference between full synthetic motor oil and 100% synthetic motor oil? Also, which group oil is Mag1 Full Synthetic 0W-20 FMX Dexos motor oil? Let’s see what they tell me. If they tell me anything at all. I have done so much reading and can’t find the difference between Full Synthetic and 100% Synthetic. My first assumption is full synthetic is Dino oil with specific additives that make it equivalent enough to synthetic base oils to call it full synthetic.