What Octane Gasoline Should the Mercedes-Benz G-Class Use?

[Juan]

The Mercedes-Benz G-Class should use 95-octane gasoline, as this fuel grade is recommended in the vehicle's official owner's manual. In addition to checking the suitable gasoline grade in the owner's manual, you can also find it marked on the fuel tank cap of the Mercedes-Benz G-Class. Typically, the appropriate 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, while those with a ratio between 10.0-11.5 should use 95-octane gasoline. If the compression ratio is higher, 98-octane gasoline is recommended. However, with the application of new technologies, the compression ratio alone cannot determine the required gasoline grade. Engines with high compression ratios can also be tuned to use lower-octane gasoline. This is because factors other than compression ratio, such as ignition timing, turbocharging technology, and Atkinson cycle technology, also play a role. Generally, the higher the gasoline octane number, the higher the octane value 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. If the Mercedes-Benz G-Class occasionally uses the wrong gasoline grade, simply switch back to the correct grade after the current tank is used up. However, prolonged use of the wrong gasoline grade can have the following effects: For vehicles designed for lower-octane gasoline, using a higher octane grade will not cause damage, but the increase in octane value can alter the fuel's ignition point, leading to delayed combustion in the engine. This results in reduced engine power and thermal efficiency, with the practical effect being poorer performance. For vehicles designed for higher-octane gasoline, using a lower octane grade can cause engine knocking. The significantly lower octane value reduces the gasoline's ignition point, causing it to ignite prematurely during the compression stroke. If combustion occurs before the spark plug fires, resistance is created during the upward stroke. This resistance makes the engine run very unevenly. Mild knocking may only increase noise without obvious engine damage, but noticeable knocking indicates severe engine conditions. The vibrations not only affect driving stability but can also cause abnormal wear on the pistons and cylinders, potentially leading to cylinder scoring in severe cases.

[DeHolden]

As a long-time Mercedes G driver, I've experienced several fueling options. When I first bought the car, the salesperson specifically emphasized using 98 octane gasoline because that V8 engine is quite sensitive - higher octane prevents knocking and makes driving smoother. I've personally tried 95 octane and felt the power was slightly weaker, with occasional minor vibrations during acceleration, so now I strictly use 98 octane. The manual clearly states a minimum of 95 octane, but for the car's longevity and performance, don't try to save money by cutting corners. Also, remember to choose reputable gas stations to avoid watered-down fuel that could clog injectors and cause expensive repairs. During regular maintenance, I always have the mechanic check the fuel system to ensure everything's working properly. In short, using 98 octane fuel gives the most peace of mind - it protects the vehicle while enhancing driving experience.

[ClaraFitz]

In my previous job, I frequently handled maintenance for Mercedes-Benz G-Class vehicles, and my recommendation is to use 98-octane gasoline directly. The engines in these rugged SUVs have high fuel requirements, and lower octane ratings can easily cause knocking. Prolonged use of 95-octane may lead to increased carbon deposits and even spark plug erosion. Check the user manual for specific recommendations—newer AMG models generally require 98-octane or higher. Avoid using 92-octane, as it could trigger the engine warning light and cause serious issues. During each service, inspect the fuel system and injection system to prevent residue buildup. While higher-grade fuel is more expensive, the trade-off for stable performance and reduced repair costs makes it worthwhile. Regular maintenance is more cost-effective than post-failure repairs, ensuring your beloved vehicle runs with greater peace of mind.

[LaAllie]

As a post-90s car enthusiast, I fuel up my Mercedes G for that cool and smooth performance. The manual says at least 95 octane, but I personally recommend 98 octane—its high octane rating pairs perfectly with turbocharging, delivering an ultra-strong kick at takeoff. Using 95 octane occasionally is fine, but it might trigger the car's computer alarm, with the app showing data fluctuations. Nowadays, you can even use the mobile app to locate nearby 98-octane gas stations, saving time and hassle. If you're on a tight budget, 95 octane works in a pinch, but don’t make it a long-term habit. Avoid randomly adding fuel additives; stick to the manufacturer’s recommendations for reliability. The more advanced the tech, the more precise care it demands.