Can You Add 95 Octane Gasoline After Using 98 Octane?
2 Answers
After using 98 octane gasoline, you can switch to 95 octane, but it is recommended to first use up the 98 octane fuel before adding 95 octane. It is advisable for car owners not to frequently switch between different gasoline grades and to stick to one type of fuel for long-term use. The differences between 98 octane and 95 octane gasoline are as follows: 1. Different octane ratings. The grade number only indicates the octane rating of the gasoline. The octane rating is determined by comparing the knocking intensity of the sample with a standard fuel mixture of isooctane and n-heptane. The volume percentage of isooctane in the standard fuel that produces the same knocking intensity as the sample is the octane rating of the sample. 2. Different anti-knock combustion capabilities. The higher the octane rating, the better the anti-knock combustion capability. 3. Different prices. Generally, the higher the grade of gasoline, the better the quality, and thus the more expensive it is.
I think this issue should be considered from a safety perspective. My car's manual recommends 95 octane gasoline, but I've also tried 98 octane without any problems. Higher octane gasoline has better anti-knock properties, but car engines are designed for specific octane ratings. Mixing different octane levels may lead to uneven combustion or slight knocking. In the long run, it might affect engine lifespan, such as increased carbon deposits or reduced fuel efficiency. The best practice is to follow the manufacturer's recommendations and avoid arbitrarily changing octane levels. If you've already filled up with 98 octane and want to switch back to 95, it's advisable to first use up the current tank before switching, and avoid frequent mixing. In short, safety comes first—don't save small amounts of money only to invite bigger troubles. The manual is the most important reference.
