When you’re standing at the pump filling your tank with “regular” unleaded gasoline, you might wonder if you should be filling it with premium gas instead. You may also think “big name” gas companies like Exxon or Shell provide higher quality gas than you would find at Wal-Mart or Kroger.
The truth, however, might surprise you.
Here’s the low-down on unleaded vs. premium gasoline: Vehicles that require premium gas should exclusively be filled with premium gas. But if your owner’s manual doesn’t mention it, your car doesn’t need it and won’t necessarily benefit from it.
The reason some cars (mainly luxury brands) need premium gas is because the engine has a high compression ratio. Lifehacker explains:
The compression ratio is the total volume inside the cylinder that is displaced when the piston moves. If you use low-octane gas on a car with a high compression ratio, it’s more likely that the gas will ignite prematurely, causing your engine to knock and rattle.
While a slight knocking sound should not alarm you, the problem comes when it gets noisier and worse—then you may find yourself in need of a new engine.
While some vehicles require premium gas, the majority of cars have a low compression ratio, which means low octane gas is more than suitable. Using premium gas won’t hurt your vehicle; however, you probably won’t see much benefit either. If your owner’s manual doesn’t say you need to use premium gasoline, paying the higher price isn’t worth it.
As far as the quality of gas, there is very little difference between what you get at an Exxon and what you get at Wal-Mart or a grocery store. All companies are forced to comply with certain requirements and regulations, which means gas quality is relatively even across the board.
If you’re concerned that your vehicle isn’t performing the way it should or hear the engine “knocking,” don’t hesitate to bring your vehicle to an experienced ASE-certified mechanic to get it checked out. It’s always better to be safe on the front end than to be stuck with pricey repairs later.
Our auto repair team at Bryant Motors can help to diagnose any possible problems and get you back on the road. Call or stop by our Sedalia repair shop today.