After an oil change is done, you assume that things are going to be fine. You hop in your car and drive off to work or the store. When you come out, there is a puddle of amber or brown liquid beneath the vehicle. Regular oil changes are necessary for the health of your vehicle, but there is always a chance that problems occur. Why is your car leaking oil after an oil change? Let’s find out.

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How Do I Know I Have an Oil Leak?

For those who have handled motor oil before, the answer to this question may be obvious. For the newer, less experienced drivers out there, you will notice a number of indicators. One of the quickest ways to figure out if oil is leaking from your car after an oil change is the indicator light on your dashboard. The light will come on only after you have lost a significant amount of oil, so when it comes on, you have to act quickly.

If that light is flashing, don’t wait. Take your car to the nearest auto body shop.

Aside from the light, the next best sign that you have an oil leak is the ground. Look for any greasy-looking puddles. Motor oil is always going to look amber, brown, or black. Is the liquid pinkish? Then your transmission fluid is leaking. A coolant leak is indicated by a greenish liquid. Both of these are very serious and should be treated with the same level of urgency as an oil leak.

The good news is that, if you notice oil on the ground, it usually points to a problem with the oil pan. Oil coming from seals may be harder to spot.

Why is Oil Leaking From My Car?

Seeing the lifeblood of your car spilled on the ground is certainly a harrowing sight. You are going to want to act immediately. However, before you start to panic, it is important that you assess the situation. It could tell you a lot about where the oil is coming from and the reason for the leak.

Loose or Incorrect Oil Filter

Should you replace the oil filter with every oil change? The answer is yes. The problem with this habit is that you increase the chance of getting something wrong during the oil change, resulting in a leak. For instance, the new oil filter you wish to install might not fit correctly. An ill-fitting oil filter is just as bad as no filter—and it will cause an oil leak.

Similarly, if the oil filter is not put on tightly, the pressure from the engine will force oil through the spaces in the filter. The recommended tightness is a ¾ turn further past the point of tightness to achieve the best seal.

Car Leaking Oil Because of Drain Plug Washer

Why is your car leaking oil after an oil change? The drain plug could be the culprit. Though the drain plug can be stripped of its threads or damaged, the more common issue is with the washer. The washer is vital because it provides a touch of spring between the surface of the plug and the bolt. The seal between the two surfaces is much more uniform, thus keeping liquid from seeping through.

However, the washer is made of a soft, squishy material. Over time and heat exposure, that material can be ripped or distorted. It is important that you routinely replace the washer with every oil change, as recommended by many automobile manufacturers.

Keep in mind that using no washer is problematic. Without the washer, the connection between the mating surfaces is going to have a bit of space. Oil will definitely leak.

Under- or Over-Tight Drain Plug

Here is another problem caused by the drain plug that could make a car leak oil after an oil change. Under- or over-tightening, the drain plug is a common problem and an easy mistake. You want to first hand-tighten the drain plug then complete the task with a wrench up to the point where it feels secure. If you don’t go far enough or proceed too far, you could end up leaving gaps or even cracking the drain pan. Both result in oil leaking from the engine.

Either way, you will need to adjust the drain plug to form a proper seal. If you have cracked the drain pan, be sure to have that replaced. Otherwise, it won’t matter how loose or tight the drain plug is. You are still going to have a leak.

Is your drain plug stuck? Check out our guide for the easiest way to remove a stuck drain plug.

Oil Reservoir is Overfilled

How much oil is too much? When you go beyond the designated line in the oil reservoir. Having too much oil is just as hazardous as having too little oil. You could end up damaging your engine. When there is too much oil, it begins to foam inside the engine, penalizing the hydraulic pressure. Your seals and gaskets are also stressed, which means that oil begins to leak.

The easiest way to check if this is the problem is to pull out the dipstick. If the oil level goes beyond the full line, you know you have a problem. Fortunately, the solution is simple. You just have to remove the excess oil, and the issue should clear up.

Wrong or Loose Oil Cap

The engine oil cap is important. Although the only job is to cover the fill tube, this works in two ways. It keeps oil fumes from escaping your vehicle and stops oil from sloshing around. Therefore, if there are oil splatters all over the engine, it points to an oil cap problem.

Sometimes, the oil cap is the wrong size. Though it’s rare, a mechanic may accidentally swap one oil cap for another. More often, the oil cap gets threaded on incorrectly, leaving little gaps for the oil to leak through. Check to see if the cap is flush with the fill tube. If it looks slightly crooked, try taking it off and putting it on correctly.

Broken Gaskets

Did you notice that the oil started leaking right after you finished putting in the new motor oil? If your car is leaking oil after an oil change, it could be a sign that there are dry seals or broken gaskets. Throughout the years, these vital seals and gaskets start to wear, degrading their sealing capabilities. When that happens, oil begins to leak into the engine.

Most gaskets and seals will last about 5 years or more. Once they start to break, however, you will need the help of a mechanic to replace them.

How to Prevent Oil Leaks After an Oil Change

Now that you know the reasons why your car is leaking oil after an oil change, let’s talk about what you can do to prevent such an issue. Every vehicle requires routine oil changes around 5,000-10,000 miles. To ensure that your engine continues to operate optimally, follow the vehicle manufacturer’s service recommendations.

After that, it is important to use the right kind of motor oil. Make sure that the viscosity grade is correct. Use high-mileage synthetic oil for cars with an odometer reading over 75,000.

No More Oil Leaks After Oil Changes

There are many reasons behind your car leaking oil after an oil change. Sometimes, it is the drain plug or an ill-fitting oil filter. If you spot oil leaking, it is important that you solve the issue as soon as possible. Most of the solutions can be done yourself, but you can also bring your vehicle to a trusted mechanic if you are unsure about what to do.

Categories: Oil Guides


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