Ron K. of Miamisburg writes by e-mail: “I have been discussing gasoline with a friend and he says that name-brand gasoline is better and that I should always use premium because it is more highly refined. I say that all gasoline comes from the same tank so buy gas where it is cheapest and use regular, and not premium, in most cars. Who is right? Thanks.”
You are, Ron. Gasoline is “fungible” meaning that if it meets specifications, such as 87 octane regular, then it is interchangeable with any other 87 octane gasoline. Once the gasoline is made, it is sent to distributors. This is where the additives are added including dyes for each brand of gasoline. So while the gasoline itself is the same, the additives can and do make a difference. Try to use “Top Tier” gasoline. For a list of stations that include an extra amount of engine cleaning additives, visit www.toptiergas.com.
Regarding the use of premium compared to regular, the only difference is the octane rating. Most vehicles are designed to operate on regular. However, some vehicles may “recommend” premium whereas others “require” premium. If the owner’s manual recommends premium or midgrade (plus), then regular can be used. However, if premium is required, then only premium should be used to prevent possible engine damage.
Have an automotive-related question? Write to Jim at firstname.lastname@example.org