What is the Difference between Regular, Midgrade and Premium Gasoline?
I will try to make this as easy as possible! There has been a lot of thought, research and testing that has gone into gasoline grades and which engines perform best with each type of gasoline.
The Facts:
1. Gasoline is rated based on octane levels.
2. In most areas of the country regular is 87 octane, midgrade is 89 and premium is 91-93.
3. Your owner’s manual and usually your gas cap, will tell you what octane level you should be using.
4. Straight-run gasoline has an octane level of about 70. Your vehicle would knock with this level.
5. Procedures to the fuel are used to increase the octane up to about 93.
6. A common misconception is the higher the octane level – the higher the quality of gasoline.
7. Anti-knock (Octane) ratings are used to measure the gasoline’s ability to resistance engine knock, rattling or pinging. These noises come from the premature ignition of gasoline.
The recommended gasoline for most vehicles is regular octane. In most cases, using a higher octane gasoline than your owner’s manual recommends offers absolutely no benefit. It won’t make your car perform better, go faster, get better mileage or run cleaner. Your best bet: listen to your owner’s manual. But using a lower octane than what is recommended can cause the engine to knock or ping in some vehicles.
All octane grades of gasoline, of all brands, contain engine cleaning detergent additives and in most cases are identical. The higher octane grade doesn’t outperform in this area. These cleaning agents protect the inside of the engine from deposit build-up.
Using too high of an octane for your engine could possibly cause damage to the emissions system. It also sends unburned fuel into the emissions system and catalytic converter and puts unnecessary stress on the system. Rotten egg smells coming from the vehicle’s tailpipe can signal the use of too-high octane gas.
In most parts of the USA, gasoline is available at not less than 87 octane, but octane levels do very from state to state so when you fill up when traveling check their ratings – you may have to adjust your selection. In higher altitude areas – such as Colorado, Wyoming, Idaho, etc. you can find and use 85 octane because that octane level performs just as well as higher octane fuels in that environment.
Regular Unleaded Gasoline –
Most vehicles have a recommendation of regular 87 Octane gasoline. In rare cases you may consider switching to a higher octane fuel if your engine knocks. Light pinning isn’t the same as knocking and if it is minimal it is not harmful to your engine. Severe knocking causes severe damage to the engine.
Mid-Grade Gasoline –
I am a sucker for this one. I say to myself “Well it must be better than regular – who wants to use regular?” Again – use this if Regular Unleaded makes your engine knock or your owner’s manual calls for it.
Premium Gasoline –
Some high performance engines perform better with high-octane fuel. Burning fuel with a lower octane rating then the engine is designed for could result in reduction of power and efficiency.
If you have a unique situation where your vehicle sits for long periods, have a vehicle that is older than 1980, or towing heavy loads for long periods of time then please feel free to call us on advice on how to handle these situations.
Tomorrow we will cover: Synthetic Oil
Happy October from the Sallas Team!
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Thanks so much ~ Carla Sallas