Should the Highlander use 92 or 95 octane gasoline?
2 Answers
The Highlander, as specified by the manufacturer, requires the use of 92 octane unleaded gasoline. 92 octane gasoline refers to gasoline with an octane rating of 92%, which is suitable for mid-range vehicles. The gasoline grade is clearly indicated on the fuel tank cap and in the vehicle's manual. The differences between 92 and 95 octane gasoline mainly lie in their octane ratings, anti-knock properties, and prices. 92 octane gasoline consists of 92% isooctane and 8% n-heptane, while 95 octane gasoline is composed of 95% isooctane and 5% n-heptane. Gasoline with different octane ratings has varying octane values; the higher the octane rating, the higher the octane value, and the better the anti-knock performance. 95 octane gasoline is more expensive than 92 octane gasoline, primarily because it contains a higher proportion of isooctane. When refueling, it is important to consistently use one type of gasoline. Mixing different grades can be harmful to the engine and fuel system. The choice of gasoline grade should be based on the engine's compression ratio, not the higher the better. Avoid blindly using higher-grade fuel.
When I first started driving the Highlander, I was really torn about this issue. Later, after checking the manual, I found that the manufacturer recommends using 92-octane gasoline. After driving it for several years, I’ve consistently used 92-octane, and the car runs smoothly with no engine issues. The octane rating mainly affects anti-knock performance, and the Highlander’s engine design doesn’t require high-octane fuel. Using 95-octane might make acceleration feel slightly smoother, but the difference is too minor to justify the extra cost. I frequently switch between city and highway driving, and 92-octane keeps fuel consumption well under control, saving a significant amount on fuel costs in the long run. Also, avoid mixing different octane ratings during refueling to prevent carbon buildup or unexpected issues. In short, following the manual is the easiest and most hassle-free approach.
