What is the optimal amount of engine oil to add?
3 Answers
Adding engine oil is generally best done to the middle point between the upper and lower marks on the dipstick. Try not to go below the middle, as high-speed driving can cause the engine to heat up, making the oil thinner, and a low oil level can reduce lubrication effectiveness. Here are some relevant details: 1. High-quality engine oil comes with multiple engine protection functions, and its formula already includes various additives, such as anti-wear agents, etc. Engine oil emphasizes the balance of its formula to ensure the full performance of all its functions; 2. Adding other additives on your own not only fails to provide additional protection for the vehicle but may also easily react with the chemical substances in the oil, leading to a decline in the oil's overall performance; 3. It is best not to mix engine oils of different brands and viscosities. This is because different brands and types of oil have different additive formulas from the manufacturers, and mixing them can lead to undesirable chemical reactions.
I've found that the best amount of engine oil to add is by referring to the MIN and MAX marks on the dipstick, usually checked most accurately when the engine is cold. Having driven multiple cars, my conclusion is: keeping the oil level between MIN and MAX, preferably closer to the MAX line but not exceeding it, is ideal. Adding too much oil can cause it to foam in the crankcase, leading to poor lubrication, engine overheating, or even piston damage. On the other hand, too little oil increases friction between engine components, potentially causing unusual noises or cylinder scuffing. My routine is to check the oil level on level ground 30 minutes after parking, pulling out the dipstick, wiping it clean, reinserting it, and then reading the level. If it's below MIN, I add oil slowly in small increments to avoid overfilling. Oil lifespan also affects how often you need to top it up, so I make it a habit to check every 5,000 km to ensure safe long-distance driving. Using a reputable oil brand with the viscosity recommended in the manual also helps save fuel and maintain the engine.
Every time I help a friend with car issues, I remind them that keeping the oil level between the MIN and MAX marks on the dipstick is ideal. The method is quite simple: park on level ground, turn off the engine, wait 10 minutes for the oil to drain back into the oil pan, then pull out the dipstick, wipe it clean, reinsert it, and check. If the oil is below the MIN line, it means there's too little and you need to add some; if it's above the MAX line, there's too much, and you should remove some to avoid foaming and damage. I recommend adding small amounts from a small bottle of oil, checking the level several times, rather than pouring it all in at once. The risks of incorrect oil levels are significant—too much oil can cause smoking and reduced engine performance, while too little can accelerate part wear. New cars especially require attention to this, and oil quality should also match seasonal changes, with lower viscosity in winter for easier starts. Make it a habit to glance at the dipstick before and after each refueling.
