Regular or Premium


1999 Buick Regal GS, manufacturer says use only premium gasoline. Is this really necessary or is regular unleaded jsut as good?


If you go to the red bar over your question and click on SEARCH, and then put “regular or premium” in the search space, you’ll get a number of discussions from previous times this question came up.


And to actually answer your question, use what the manual recommends. If regular was just as good, don’t you think Buick would have said ‘use regular fuel’?


When the manual says to use only premium then that is what it means. Using regular can damage the engine.

Often the manual will say that premium is recommended. In that case you can use regular, but it will cost you in reduced performance and often in mileage, so you may not save any money by using regular. Those cars have a sensor to detect the effects of regular and to dumb down the engine when you use it.

I have to question anyone who buys a car that requires or recommends premium and then wants to use regular.