Knowing how often to check oil in your vehicle can help prevent engine problems. Most vehicle owners know they need to change their oil at specific mileage intervals, but how often should you check the engine oil level between oil changes? As with most car maintenance questions, the answer depends on several factors.
How often should you check the engine oil level?
A good rule of thumb is to check your oil every 30 days. This is an addition to changing your oil at factory-recommended preset intervals or relying on your vehicle’s electronic oil sensor to indicate when the next oil change is due.
You may want to check it more or less often depending on factors such as:
- Age of vehicle. If your car is newer (less than 5 years old), has less than 75,000 miles and has been properly maintained, you can check your oil less often.
- Mechanical issues. If you know your vehicle has mechanical issues that cause it to use more oil, you may have to check for engine oil level weekly or even daily.
- Driving style. If you drive your vehicle in an aggressive manner or put it under a consistent load more often (such as towing), you may want to check your engine oil level more often.
- High mileage. If your vehicle is high mileage, you definitely want to check your engine oil more often than a vehicle that has lower mileage.
- Oil type. If you use conventional oil, you may want to check your oil more often.
Most modern cars have a vehicle maintenance system that measures everything from your driving habits to the temperature outside in order to determine when your vehicle is due for an oil change. These systems also alert you if your vehicle’s engine oil falls below a certain level. Most modern vehicles also use synthetic oil designed to go longer between oil changes and provide a higher level of protection than conventional oil.
In the days before oil sensors and the widespread adoption of synthetic oil, many drivers would adhere to the 3,000-mile rule: Whenever the odometer would click over another 3,000 miles, it was time for an oil change. Today this is typically considered excessive. Modern vehicles using synthetic oil can sometimes safely go as many as 10,000 miles between oil changes.
If your vehicle is losing oil, the engine may not receive adequate lubrication or adequate cooling. This can lead to major issues ranging from blown gaskets all the way to a complete rebuild or the need for a new engine.
How to check your oil
Opening up the hood of your vehicle and taking a look at the engine can be intimidating, but with a bit of know-how, it’s easy to check your engine oil:
- Ensure your vehicle is turned off and the engine is cold (i.e., it hasn’t been running for a while). This is essential for an accurate measurement.
- Reference your owner’s manual to locate the engine oil dipstick in the engine bay. This simple piece of metal is designed to help you measure the amount of oil in your engine with a quick glance. The handle is typically made of brightly colored plastic to make it easier to spot.
- Remove the dipstick from the engine and use a shop rag or towel to wipe it clean.
- Reinsert the dipstick fully into the engine.This helps ensure an accurate measurement because the dipstick will collect oil during normal engine operation and the oil level fluctuates when the engine is turned on.
- Remove the dipstick again and check the hash marks on the side of the dipstick against where the oil is on the dipstick. Typically, most dipsticks will have a low and full mark to indicate where optimal engine oil level should be.
- As long as your engine oil level is between the low and the full, this is generally considered normal.
- Also, check the quality of the engine oil and take note of engine oil that is extremely dark or looks like a milkshake. In either case, you may be looking at a serious problem. The “milkshake” look comes from the mixing of oil and coolant, typically as a result of a cracked block or blown head gasket. Extremely dark oil indicates that the engine oil is collecting excessive carbon or debris from inside the engine and could be a result of failing components.
What to do if you’re low on oil
If you determine your engine oil level is low, take action to avoid potentially serious consequences down the road.
An engine burns oil in its normal operation, and it is normal to have some engine oil loss between oil changes. The oil darkening or appearing dirty between oil changes is normal, too. This is what engine oil is designed to do, but there are limits to how dark engine oil should be.
The first thing to do if your engine oil level is low is to refill the engine oil to an acceptable level:
- Check your owner’s manual to determine the proper oil to put inside of your vehicle’s engine. Using the correct grade is vital, but conventional and synthetic oils can be mixed safely if you only have one or the other.
- Locate the oil filling cap on top of your vehicle’s engine and remove it.
- Use a funnel to pour the engine oil into the engine. Take care not to spill any on the engine itself. If you do spill, be sure to wipe it up immediately.
- Depending how low your engine oil was when you checked the dipstick, add oil a little bit at a time. A good rule of thumb is to add it in half a quart at a time.
- Repeat the steps above to check the engine oil level once you have poured in your first half-quart.
- Repeat until your engine oil level is noted as full on the dipstick.
Once you top off the oil, keep a close eye on the oil level. If your vehicle is older (75,000 miles or more), it may simply burn more oil than when it was new.
If your vehicle is newer and is burning more than a quart every 1,000 miles, something could be wrong. You should also be on the lookout for other signs of excessive oil usage, such as blue-tinted smoke out of the exhaust pipe. If any of these conditions present themselves, get your car to a qualified shop immediately.