I don't know anything about cars and I am just fortunate to have learned how to drive. My husband falls in the same category. We have been advised many times by (different) gas station attendants to fill our tank with premium instead of the prescribed unleaded gasoline. Their reason is the power that the premium gas could give the engine. In the long run, it is more economical to use premium gas than unleaded gasoline. But our apprehension is the complication that might occur. What if the car's engine develops a problem? There's even a sticker in the gas tank that says "unleaded only" so logic tells us to just follow what the sticker says.