* Regular (87 octane): This is the cheapest option and is perfectly suitable for the vast majority of vehicles. Check your owner's manual; if it specifies regular unleaded, stick to it. Using a higher octane fuel won't provide any benefit and is a waste of money.
* Mid-grade (89 octane): This is a compromise between regular and premium. Some cars might see a slight performance improvement or slightly better fuel economy, but the difference is often negligible unless specified by the manufacturer.
* Premium (91 octane or higher): This is the most expensive option. It's only necessary if your car's owner's manual specifically recommends or requires it. High-performance engines or those with high compression ratios often need premium gas to prevent knocking (pre-ignition). Using premium in a car designed for regular will not improve performance and is wasteful.
In short:
* Consult your owner's manual: This is the most important step. The manual will clearly state the recommended octane rating for your vehicle. Follow this recommendation.
* Higher octane doesn't automatically mean better: It's only better if your engine needs it.
* Focus on quality: Regardless of the octane, choose gasoline from reputable brands to minimize the risk of impurities that could harm your engine.
Using the wrong octane can potentially cause engine damage in some cases, particularly if you consistently use a lower octane than recommended. Always prioritize the recommendation in your owner's manual.
