A lot of drivers these days are filling their tanks with “regular” gasoline, even if the car requires premium.  As we saw earlier, Cadillac tried to prepare its new SRX for that, but didn’t succeed, at least not initially.  After seeing that, I suspect a few more people will start using the fuel required for their car.

The big argument people have when I ask why they use lower octane fuel, is cost.  They will tell me they’re just trying to save some money.  Well, I have news for them, and anyone else who wants to “save a few bucks” on gas: you’re not saving much, if anything, and all that cheaper gas can lead to premature engine wear and failure!  Remember when reading the numbers below that new engines typically run in the thousands, anywhere from $2,500 to $12,000, depending on the vehicle.

Let’s take a look at the big picture.  Besides the Smart ForTwo, I can’t think of any other inexpensive car that requires premium.  Perhaps the Mini Cooper, but that car starts at $20k for a stripped base model.  Add a few options to it, and you’re getting close to the $30k mark.  Basically, cars that require premium fuel generally cost more, and if you can afford the car payment, gassing up shouldn’t be an issue either.  Even if you buy a used luxury car that retailed new for $50-60,000, you still have to keep up with the maintenance (another thing a lot of people forget about when shopping for a car).

Breaking down the supposed savings, the average difference between regular gas and premium is around $.30, depending on where you live.  Here in the Washington, D.C. Metro area, regular gas is about $2.85 and premium is around $3.10, per gallon.  that’s only $.25, but we’ll round up, taking into account a fuel price spike.

If your car gets 20mpg average (combined city/highway), and you drive 20,000 miles a year, which is more than average, you’ll use 1,000 gallons of fuel per year.  At a difference of $.30 per gallon, you’ll spend $300 more per year on premium than you would have on regular.  That’s less than the average car payment, and broken down, it’s about $5.00 per week.  That’s one cup of coffee at Starbucks, per week, and you can afford that premium gas your car says it requires.

As an example, my own 2010 Nissan Maxima was certified by the EPA to get 18 mpg in the city, and 26 mpg on the highway.  It also says in the owner’s manual (right) that 91+ octane fuel, also known as “Premium Unleaded” at the gas pump, is recommended for maximum performance.  The sticker price for my Maxima was close to $40,000, so if I drive 100,000 miles over 5 years, that still only adds up to about $1,500 of extra fuel costs, maybe closer to $2,000 if the price of gas increases (and it assuredly will).  So, up to 5% of the sticker price of the car could be spent on premium fuel versus regular – that’s a no-brainer to me.

In the end, the choice is of course up to you, but I recommend you use whatever fuel the manufacturer recommends or requires.  It just isn’t worth the headache of needing expensive repairs, is it?

by John Suit

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