It can be highly alarming if you notice that your car has an oil leak. Worse yet, if you recently brought your Subaru in for an oil change, it’s easy to wonder if something was broken or improperly installed during this routine maintenance process. But why does oil leak after an oil change?
An oil leak after an oil change often happens because a component was installed too loosely or overtightened. This issue needs to be addressed if you want to keep your engine in optimal condition. Luckily, identifying the cause and resolving the issue is often extremely simple.
In this article, I’ll explain everything you need to know about an oil leak that starts after an oil change on your Subaru. In addition to key insights into whether it’s normal for oil to leak after a change, I’ll also explain the most common reasons for the leak and whether you’ll need to take your car back to the shop.
Is It Normal for Oil To Leak After an Oil Change?
It is not normal for oil to leak after an oil change. However, it’s common to observe leaking after an oil change if a mistake was made during the process. Issues with the oil filter installation and with the drain plug seal are known to be frequent causes of oil leaks.
Of course, it’s always possible that another underlying issue might be causing the leaking oil you observe.
In fact, the issue can sometimes be completely unrelated to your car’s recent oil change. Identifying and addressing the leak’s source is essential for ensuring your vehicle can continue functioning as intended.
It’s important to note that oil leaks can happen with any car. For example, while BMWs offer superior engineering and performance, they’re just as prone to oil leaks as any other car if maintenance isn’t completed correctly.
Ensuring you only work with a reputable auto technician could save you from unintentional disasters later on.
Why Does Oil Leak After an Oil Change?
Oil commonly leaks after an oil change because the components that store and distribute the oil throughout your car’s engine are broken or improperly installed. The two most common issues that cause oil leaks are improperly installed oil filters and loose oil drain plugs.
Of course, there are other reasons your car might leak oil after an oil change.
Corrosion, cracking, or other forms of damage can impact the performance of the rings, valve seals, or gaskets that come into contact with the oil. When damage to a component breaks the airtight seal, an oil leak can quickly form.
You can learn more about identifying the signs of oil leaks on a Subaru from my article here.
It’s worth noting that the best way to prevent these issues is to have your Subaru regularly maintained by an experienced and credible auto technician. While this regular upkeep might cost more upfront, it will save you a lot of energy and money in the long run.
Improperly Installed Oil Filter
For the oil filter to have an airtight seal, it must be installed correctly. Unfortunately, it’s very common for drivers to notice oil leaks after this component is improperly installed. The issue often arises because the incorrect filter is installed or the oil filter isn’t fastened to the correct degree.
You should verify that the oil filter is designed for your vehicle model. As for tightness, it’s generally recommended that an oil filter is tightened by hand just until it sits properly. Then, an extra quarter turn is recommended to ensure that the filter is correctly locked into place.
A Loose or Over-Tightened Oil Drain Plug
One of the most common causes of an oil leak directly after an oil change is a loose or over-tightened oil drain plug.
If you can unscrew the oil drain plug by hand, it’s too loose. The oil drain plug is over-tightened if it won’t budge even when you use a socket wrench and a hefty amount of force.
Ideally, you should make sure that the oil drain plug is tightened just until it can be removed with a wrench but won’t budge otherwise. If your oil drain plug was tightened too far, you must verify that the threads inside the oil pan are still functional and make additional repairs if necessary.
Double Filter Gaskets
Ordinarily, the filter gasket is meant to be removed with the oil filter during an oil change. If the filter gasket isn’t removed, layering the new filter gasket and oil filter on top of the old gasket will create an improper seal. As a result, your car’s engine will begin to leak oil.
You should always make sure that the old filter gasket is completely removed before a new oil filter is added during an oil change. If you suspect that a double filter gasket is the cause of the leak, the issue is, fortunately, easy to confirm with an inspection.
It’s not just the improper installation of a filter gasket that can cause catastrophic leaking. Many of the gaskets that your Subaru engine relies on are known to lose their airtight seal occasionally. This typically happens as a result of natural wear and tear. Luckily, resolving the issue with a repair is simple once you know which gasket is leaking.
- Rocker cover gasket leak. You may notice a puddle of oil around the spark plugs and cylinder head indents or under the engine’s center. A filter gasket leak in this area is usually also accompanied by a burning smell and gunk buildup on the top of the engine.
- Camshaft gasket leak. These leaks are also known to cause puddles to form under the engine. If you suspect that this gasket might be causing your leak, you should check to see if a puddle has formed under the rocker cover.
- Oil pan gasket leak. This leak isn’t known to be especially distinct. If you notice that puddles of oil are dripping into strange areas under your engine, you should verify that the oil pan gasket is secured properly.
- Front cover gasket leak. If a leak is coming from the front cover gasket or front main seal, you’ll observe a puddle of oil forming towards the front of the engine or over the drive belt.
- Head gasket leak. These usually drip in a similar way to a rocker cover gasket leak. This type of leak is usually also accompanied by white smoke pouring out of your car’s tailpipe as a result of coolant leaking into the combustion chamber.
- Rear main oil seal leak. You might notice oil dropping from the area between the transmission and the engine. You may also notice that a lot of oil has dripped onto the flywheel.
When first installed, all of the components that allow your vehicle to move oil and lubricate the engine are extremely airtight. Unfortunately, this quality doesn’t last forever. It’s common for drivers to notice an oil leak after an oil change if their Subaru is aging. Working with a technician to identify the source of the leak and replace the component is the most effective method to resolve this issue.
It’s common for oil to start leaking after an oil change if too much oil is added to the reservoir. While the leaking oil from an overfilled reservoir might be as alarming as any other source of leaking oil, it’s actually one of the most mundane causes of this common issue. Consider draining the excess oil by using the oil plug.
Should I Take the Car Back to the Shop if It is Leaking After an Oil Change?
You should take your car back to the shop if it is leaking after an oil change. Whether you drive a Subaru or a BMW, your car relies on having the proper internal lubrication from the oil to function.
If your car loses too much oil from a leak, you won’t just be wasting money — you’ll also put your engine at risk of catastrophic damage.
Inside the engine, thousands of minuscule piston movements repeat every second to generate the mechanical energy necessary to put your car into motion. These repeated motions can only operate so smoothly because the pistons are well-lubricated and have the correct amount of friction. Without enough oil to lubricate the cylinders, the engine will quickly fail.
Oil serves an essential role within your vehicle. If the engine cylinders aren’t properly lubricated, the pistons will generate too much heat and begin to warp or fail. If the pistons or cylinders are warped or melted, the amount of compression generated by the piston won’t be enough to keep your car moving.
As you can see, it’s absolutely essential to take your car back to the shop if it leaks after an oil change. If you decide not to address the leaking oil, you will risk harming the performance of your car’s engine. You could potentially cause your car to stop working altogether.
If you are looking for a new mechanic, check out these 5 Things To Look For When Choosing A Mechanic For Your Subaru.
Cars are complex machines that rely on many components running as intended to function. Some components are more critical than others — and there’s no doubt that the engine is among the most important.
While saving your concerns about an oil leak for another day might be tempting, you should always address the issue as soon as possible to ensure that your car can stay at top performance.