What type of gasoline should be used for the Mercedes-Benz GLC?
3 Answers
The Mercedes-Benz GLC requires a minimum of 95-octane gasoline, as recommended in the user manual. Of course, using 98-octane gasoline is also acceptable. Generally, it is not advisable to use gasoline with a lower octane rating than what the manufacturer specifies or recommends. Long-term use of incorrect gasoline octane ratings can have the following effects: Using a higher octane gasoline in a vehicle designed for lower octane will not cause damage, but the increase in octane can alter the fuel's ignition point, leading to delayed combustion in the engine. This results in reduced engine power output and thermal efficiency, with the practical effect being poorer performance. Using lower octane gasoline in a vehicle designed for higher octane can cause engine knocking. This occurs because the significantly lower octane rating reduces the fuel's ignition point, causing premature ignition 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. If the knocking is mild, it may only increase noise without significant engine damage. However, noticeable knocking indicates severe engine conditions, affecting not only driving stability but also causing abnormal wear on pistons and cylinders, and in severe cases, cylinder scoring.
I've been driving a Mercedes-Benz GLC for several years and have gained considerable experience with refueling. Both the fuel cap and the owner's manual clearly state that 95-octane or higher gasoline is required. I usually stick to 95-octane, and a full tank typically gets me over 600 kilometers. I remember one time at a county gas station where only 92-octane was available. Reluctantly, I filled up with it and immediately noticed severe engine vibration and slower throttle response. Later, I specifically asked a 4S technician about it, who said occasional use wouldn't cause major issues, but prolonged use of lower-octane fuel could increase carbon deposits and potentially damage the high-pressure fuel pump. Now, I always go to reputable gas stations for 95-octane. Although it's more expensive than 92-octane, it's better for the car, and in the long run, it actually saves on maintenance costs. I recommend that car owners get into the habit of checking the fuel cap label and never compromise on fuel quality just to save a few bucks.
As someone who prioritizes vehicle maintenance, I believe using 95-octane gasoline for the Mercedes-Benz GLC is the most prudent choice. The high-compression turbocharged engine requires high-octane fuel to maintain stable combustion, and 95-octane effectively prevents knocking. While the engine control unit can adjust ignition timing when using 92-octane long-term, the engine operates in suboptimal conditions, increasing fuel consumption by about 5% and causing catalytic converter carbon buildup. Compared to 98-octane, I've observed better power response during uphill climbs in high-altitude areas, but for daily commuting, 95-octane offers better cost-effectiveness. During each maintenance service, technicians always check the fuel filter condition - with consistent 95-octane use, the filter typically lasts five years without replacement.
