you use what gets you the best mileage only way of really knowing which is by testing a few brands and type best way to do this is by filling at place you always stop at with highest octane they have set mileage drive til you need to refill then write down how many miles then fil with next lower type octane do it again one that you get best miles rigth one to use at that store or brand then stop at place you sometimes stop at do the same thing since not all fuels are the sme and not cars drove the same only real way to know which your car likes the best is by testing a few its like my nissan greats grerat mileage with shell high octane but gets the same with mobil regular and most of time the higher the octane the better the miles and running
Regular.
I think you mean premuim or regular.
Both octanes are unleaded.
Premium is a total waste of money if the engine is designed for Regular gas. Premium has no more power and acutally will get stale quicker. \----
Only if one has an engine that the enginiers demand premium then it must be used or todays engines will retard their timing to avoid piston knock and the engine will sludge up.
Dont ever think you know more than the men that wrote the manual.
Regular.
I think you mean premuim or regular.
Both octanes are unleaded.
Premium is a total waste of money if the engine is designed for Regular gas. Premium has no more power and acutally will get stale quicker. \----
Only if one has an engine that the enginiers demand premium then it must be used or todays engines will retard their timing to avoid piston knock and the engine will sludge up.
Dont ever think you know more than the men that wrote the manual.