What Color Should Engine Oil Be?

by Alastair | Last Updated: August 17, 2023

If you want to keep your car running for a long while without any problems, then you need to change the oil. That is a fact of car ownership that you can’t ignore. You wouldn’t last long without blood, your car won’t last without oil. It’s that important. Aside from routinely changing the oil, you can monitor the color of the engine oil and gain valuable insights into its condition, as well as the overall health of your engine. So, what color should engine oil be ideally and what do other colors indicate? Let’s find out.

What Does Oil Color Tell You About a Car?

As mentioned above, checking the engine oil color is a quick method of understanding the condition of your vehicle. The color can even give you a glimpse into issues like coolant leaks or contamination—if you know what to look for.

Engine oil, as you may be aware, changes as it ages. Unfortunately, engine oil doesn’t age like fine wine. It goes through additive degradation, gets filled with pollutants and grime, and is also exposed to high heat, which changes its viscosity over time. That said, while looking at the color could help you better diagnose an issue or give you a clue as to how long you can go without an oil change, it is not a sole determinant. You should always consider the mileage on your vehicle, recommended oil change intervals, and your daily driving conditions.

What Color Should Oil Be On The Dipstick?

Ideally, fresh engine oil should appear in various shades of amber, depending on the type of oil used and the age of your vehicle. The oil may be slightly darker if you use specific additives, but immediately after an oil change, it should retain an amber color for a considerable amount of time. This amber color is the desired state for your engine oil.

Over time, engine oil absorbs combustion by-products and contaminants, which can cause it to darken. The darker color indicates that the oil is performing its intended function by collecting these impurities. However, it’s important to note that the rate at which the oil darkens can vary depending on factors such as driving conditions and the type of engine.

For diesel engines, it is common for the engine oil to turn black relatively quickly after an oil change. Therefore, it is crucial to adhere to the recommended maintenance schedule for diesel engines. This guide primarily focuses on gas engines.

If you need help finding and reading the dipstick, check out “How to Read the Oil Level on the Dipstick,” or watch the video below:

Dipstick Oil Color Chart

Let’s take a closer look at the different engine oil colors you may encounter and what they signify. Use the image above to cross-reference the color you see on your car’s dipstick. This will help you to better determine which color you are seeing or what it means.

Amber

Clean, amber-colored oil is considered the ideal color for engine oil. It indicates that the oil is relatively free of contaminants and is performing its essential functions, such as lubricating engine components and providing protection against wear and friction. When you observe amber-colored oil on the dipstick, it suggests that the oil is still in fresh or good condition and can continue to be used. Generally, you can assume you still have around 3,000 to 5,000 miles worth of driving before you will need to change this batch of oil.

Dark Brown or Black

Many people are alarmed by the sight of dark brown or black oil on their dipstick, but you don’t have to be. When the engine oil color is dark brown or black, the oil is doing its job and picking up contaminants and impurities from the engine. Over time, as the oil circulates through the engine, it collects dirt, debris, and by-products of combustion, like metal shavings. By consistency, you can tell when your dark oil is still good versus going bad.

Some impurities will cause the oil to grow black and thicken up, becoming sludgy. In this event, you will want to change your oil sooner than later. On the other hand, if the oil is black but remains thin (not clinging to the dipstick), this is considered normal, particularly when additives have been used.

Creamy or Milky

Does the oil on the dipstick have the appearance of a chocolate milkshake? Any time the engine oil color is frothy or milky, you need to take immediate action. This color indicates a potential issue with a blown head gasket, which allows coolant to leak into the oil. The presence of coolant in the oil can lead to significant engine problems and costly repairs. In addition to the milky appearance, you may notice a creamy buildup on the oil filler cap, white smoke coming from the exhaust, and the engine potentially overheating. Do not delay repairs if you notice these symptoms. Continued driving with a blown head gasket can result in severe damage to the engine.

That said, creamy oil may also be caused by water contamination instead of a coolant leak or head gasket failure. If that seems to be the case, you only have to change the oil to solve the problem.

Rusty

Older, high-mileage engines or those that have been exposed to humidity may end up with rust-colored engine oil. The main reason is condensation building up on the dipstick and diluting the darker brown of your engine oil. If you suspect that, run your car for a little while, let it cool, and then do another dipstick reading. See if the color is the same.

The other possibility is leaking automatic transmission fluid. When engine oil and transmission oil meet, a rust color is created. It’s advisable that you schedule an appointment with an automotive technician as soon as possible. This could be pointing to issues with either the cooling system or transmission. Problems, like those need to be addressed before permanent damage, is caused.

Now You Know What That Engine Oil Color Means!

Knowing engine oil colors is a crucial yet overlooked component of taking care of your vehicle. Being able to tell the difference between fresh amber oil and dark brown oil that is still good is key. Furthermore, you know how leaks change the engine oil color. By regularly checking the oil level and its color, you can identify potential problems more quickly and keep your car running for longer!