5 Signals when Engine Oil should change in Car

The engine oil in your car is the most important thing for keeping it running smoothly. It prevents friction, wear, and rust on the metal parts that make up your engine. Over time, these components can become dirty or worn out if they are not properly lubricated. Once this happens you will notice a change in performance of your vehicle – which is why it’s important to know when to change the oil.

Dave, lube expert from davesoilchange.com talks about 5 different signs that indicate you need to change the engine oil in your car, including:

  • mileage,
  • age of the vehicle (or miles driven),
  • changes in warmth/coolness of motor compartment,
  • coloration changes with exhaust fumes seen underhood near tailpipe
  • and deposits on windshield & headlights during rain/dusk.

1. Sign – Mileage


This is the most common sign that you need to change your engine oil. Engine oils are made up of molecules which break down over time, and when they do this it creates deposits in your engine- which can damage parts if not removed.

The number one way to tell if you’re due for an oil change is based on how many miles or kilometers have been driven since last change. Most vehicles come with a sticker inside the driver’s side door jam suggesting vehicle owners replace their motor oil at 3000-mile intervals (for example). But some manufacturers suggest more frequent changes than others so be sure to check your owner’s manual before making any assumptions! If there isn’t a suggested interval included in your handbook, every other year should suffice as a rule of thumb.

Tip: A great way to keep track of your oil changes is to make note of the date and mileage when you last do it in a calendar or on your phone! This will help remind you when it’s time for the next one.

If you have driven more than the recommended number of miles since your last change, don’t wait until you see physical signs that indicate an issue- take your car into a mechanic and get it changed as soon as possible! Continuing to drive with worn down engine oil can cause significant damage over time which could lead to costly repairs.

Older cars (> 20 years) should adhere to stricter maintenance schedules since their lubricants break down much faster than newer models.

If you’re not sure how to change your engine oil, most mechanics will be more than happy to do it for you- and it’s a service that usually doesn’t cost too much. So don’t put it off.

As a general rule of thumb, changing your car’s engine oil every:

  • 3000 miles if the driver is using conventional motor oil or
  • 5000 miles if the driver is using synthetic blend or full synthetic oils.

2. Sign – Oil Change If Car Not Used


Just like people, cars have an expiration date. Well, not really- but after a certain number of years (or miles driven), it’s time to change the engine oil regardless of how many miles are on the odometer. The reason for this is that car parts start to wear down over time and they need proper lubrication in order to function properly.

If your car has been around for awhile or has aged past 100k miles then it may be time to consider changing the oil. Even if your car doesn’t have high mileage, it’s still important to change the oil at least every other year or so to keep everything running smoothly.

If a car is older than 100k miles or has been around for awhile, it may be time to consider changing the engine oil regardless of how many miles the car has on it. This is because over time components can become dirty and not function as well without proper lubrication- which can cause problems down the road.

Tip: Keep track of when major services such as tune-ups and oil changes should be performed by writing them down in your calendar or on your phone. This will help you stay on top of your car’s maintenance and avoid any costly repairs in the future.

3. Sign – Warmth/Coolness Of Motor Compartment


A good indication that you need to change your oil is if it starts getting noticeably warmer than usual. If the engine compartment feels hotter than normal when the car is running, this could be a sign that there’s too much dirt in the lubricants and they need to be changed soon before major damage occurs.

When changing your own motor oil at home, make sure to use proper tools- specifically an auto jack with appropriate stands made for your specific vehicle model (not all jacks are created equal) or else you risk causing more harm than good!

Changing automotive fluids like motor oil can seem intimidating but don’t let fear keep you from maintaining your ride. Just take things slowly and educate yourself on how everything works beforehand so you know what to expect.

Another sign that you may need to change your engine oil is if the car starts feeling unusually cool when it’s running. If this happens, it means that the oil has become too thin and isn’t providing enough lubrication for the moving parts- which can also cause problems down the road.

4. Sign – Coloration changes


If you take a look under the hood near the tailpipe and see changes in coloration with your exhaust fumes, this can also be a sign that your engine oil needs to be changed. This usually happens when there is an excess of fuel in the system which then causes the oil to turn black very quickly.

When looking at exhaust fumes under the hood near the tailpipe, coloration changes can indicate that engine oil in car needs to be changed. This is usually due to an excess of fuel in the system which then causes it to turn black very quickly.

5. Sign – Deposits on windshield & headlights during rain/dusk


Another common sign when your vehicle may need a change in motor oil are deposits on windshield and headlights during rain or dusk. If you notice this happening more often than usual, there could potentially be water or other contaminants affecting how well the lubricant works at preventing rusting and corrosion within the engine block parts.

When deposits form on windshields and headlights during rain or sunset (at night), it can signal that motor oil should change soon- since this is caused by water or contaminants that the lubricant isn’t able to prevent.


In conclusion, knowing when to change your car’s engine oil is important for keeping it running smoothly and preventing any long-term damage. By being aware of the five signs mentioned in this blog post, you can be proactive about changing your oil before it becomes a bigger issue.