What grade of gasoline is suitable for the Highlander?

[ODamian]

The Highlander should use 95-octane gasoline. This fuel grade is recommended in the vehicle's official owner's manual. In addition to checking the appropriate gasoline grade in the owner's manual, you can also find it marked on the fuel tank cap of the Highlander. Typically, the gasoline grade can also be determined based on the engine's compression ratio. Vehicles with an engine compression ratio between 8.6-9.9 should use 92-octane gasoline, those between 10.0-11.5 should use 95-octane, and higher compression ratios may require 98-octane. However, with the application of new technologies, the compression ratio alone cannot determine the suitable gasoline grade, as high compression ratios can also be tuned to use lower-octane gasoline. Other factors such as ignition timing, turbocharging technology, and Atkinson cycle technology also play a role. Generally, the higher the gasoline grade, the higher the octane number and the better the anti-knock performance. 92-octane gasoline contains 92% isooctane and 8% n-heptane, while 95-octane gasoline contains 95% isooctane and 5% n-heptane. Occasionally using the wrong gasoline grade in the Highlander only requires switching back to the correct grade after consumption. However, long-term use of the wrong gasoline grade can have the following effects: For vehicles recommended to use lower-octane gasoline, using higher-octane gasoline will not cause damage, but the increased octane number can alter the fuel's ignition point, leading to delayed combustion in the engine. This results in reduced engine power and thermal efficiency, manifesting as poorer performance. For vehicles recommended to use higher-octane gasoline, using lower-octane gasoline can cause engine knocking. Due to the significantly lower octane number, the fuel's ignition point decreases, causing premature ignition during the compression stroke. If combustion occurs before the spark plug ignites, resistance will arise during the upward stroke. This resistance makes the engine run very unstably. Mild knocking may only increase noise without significant engine damage, but noticeable knocking indicates severe engine conditions, affecting not only driving stability but also causing abnormal wear to pistons and cylinders, and in severe cases, cylinder scoring.

[VanSimon]

I've been driving a Highlander for several years and always insist on using 95-octane gasoline. Toyota's manual clearly recommends this grade because the engine has a relatively high compression ratio. Using 92-octane fuel may cause knocking, noticeably reduced power, louder engine noise, and higher fuel consumption. I usually choose 95-octane fuel from reputable gas stations, which makes the car run more smoothly and prevents minor issues from accumulating into major problems. A friend of mine had to repair his car several times after using the wrong fuel, costing a lot of money. Therefore, I believe strictly following the manual not only saves hassle but also extends the vehicle's lifespan. Additionally, driving habits are important—avoiding sudden acceleration can reduce engine strain. Checking the fuel condition during maintenance can also help detect potential issues early.

[Jasper]

From a technical perspective, the Highlander's engine requires high-octane 95 gasoline to prevent knocking, which is a phenomenon caused by sudden pressure spikes during fuel combustion leading to abnormal noises and engine damage. Using 95-octane fuel allows the ECU to optimize ignition timing, enhancing power and efficiency. Conversely, using 92-octane fuel would cause the ECU to retard ignition to prevent knocking, but this increases fuel consumption and emissions. Given the inconsistent fuel quality in the Chinese market, I always use 95-octane gasoline to protect the pistons and spark plugs from carbon buildup. This practice is crucial for long-term vehicle health, especially during high-load driving conditions.

[RoseRose]

In terms of fuel efficiency, I always use 95-octane gasoline for my Highlander to ensure optimal combustion efficiency, reduce fuel consumption, and minimize exhaust emissions for environmental friendliness. The correct octane rating allows the engine to perform at its best, enabling me to travel further on each tank, which is better for both my wallet and the planet. I choose 95-octane fuel from reputable gas stations to enhance reliability and reduce resource waste. I advocate for this practice to promote sustainable mobility together.

[LeJayden]

Safety first is my driving principle, so I use 95-octane gasoline for my Highlander to prevent knocking that could damage components and avoid risks of sudden stops or power interruptions, especially important for stable output during high-speed driving. I've seen a friend's engine develop abnormal noises after using lower-octane fuel, which affected concentration and posed dangers. Therefore, I recommend regularly checking fuel quality and consistently using 95-octane to ensure the engine remains in good condition, guaranteeing driving safety and reducing maintenance hassles.