Skip the auto shop - Our mechanics make house calls

Q: Is it bad to over-fill engine oil?

asked by on

Is an over-filled engine oil bad? I've had my Mazda taken to the dealership for fluid replacement and each time I noticed that the oil level was above the second mark.

Yes it is bad. Engines are made for a certain amount of oil. If you put too much oil, it takes up space that wasn’t taken up before and can cause compression problems that can blow seals out.

You’d want to empty it out so that it’s just at the full level and go someplace else to get your oil changed, because will need to be at the full level. That’s what a pro does. I always look them up. I don’t even trust a gas sign. I look at my computer and if it says 3.4 quarts, I put 3.4 quarts. You want to be a pro when you’re changing it and not put the wrong amount in because it can ruin it.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Is it bad to over-fill engine oil?

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Front seal leak in minivan's transmission - 1997 Ford Aerostar

Hello. It sounds like your transmission either did not get completely full of fluid after the service or it is leaking fluid again. To check the transmission fluid, start the car and leave it in park. Next pull out...

Q: AC compressor idler pully won't spin

The AC compressor pulley or compressor clutch has a bearing inside of it that enables the pulley to spin without the clutch being engaged. When the air conditioning is turned on inside the vehicle the compressor clutch will engage and...

Q: How often to change struts

I thought streets are bad in Houston but I guess some places are even worse. It depends on how they are worn out and the car type. Some cars have stronger struts. Take Toyotas for example, they come with pretty...

Related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...