We all have, at one point or another, wondered if that car sitting in your garage REALLY requires the premium gas or if maybe, just maybe, you can get by with regular. First of all you have to learn how to read between the lines..when a manufacturer “RECOMMENDS” a certain octane rating, it doesn’t mean its “REQUIRED”. With gas prices hovering around 3.39 for regular and 3.59 for premium here in Southern California, you just can’t help but watch your wallet get thinner and thinner every week. Assuming you fill up for 15 gallons each time, you’re looking at $3 difference between regular and premium. Thats good for a couple of Chalupas right there! Do this once at week and you’re looking at around $12 bucks a month…so over a course of the year, you’ll have $144 (give or take) worth in savings by opting for regular over premium. Of course my calculations are rough estimates, it is safe to assume your savings will much more due to daily price fluctuations and the fact that you don’t always gas up at the same station.
The safest way to make sure its safe to downgrade to regular is to check your car’s manual. If they say 89 octane gas can be used with some minor “hit” in performance/mileage, then you may want to do it. If 91 octane is required, then you don’t have a choice but to open that wallet further.
I did a little testing on the cars I’ve leased in the past and recorded them one fueleconomy.gov. On my 03 Audi A4 Quattro, I was averaging about 20.1 mpg on mixed driving, the normal average being 21 mpg. Minor hit for using regular over premium. Now on the 2007 TSX, I was getting 26 mpg on regular, with the average being 23mpg in mixed driving. Both cars recommended premium, but it seems the Audi’s performance took a bigger hit, probably because it was turbocharged. So if you’re leasing, feel free to just gas with regular if your car allows it. If you buy, I would probably recommend you to stick with the recommended grade since you are OWNING the car and probably want to baby it so it lasts.