Why Do Cars Leak Oil and What Should You Do About It?

We’ve all been there: you’re walking up to your car in the parking lot and you notice fresh drops of liquid under it. Your car has been running great, so you quickly dismiss the possibility of it being anything concerning. You notice an ever-growing collection of dark droplets on your driveway over the next several days, and you come to terms with what you’ve been denying. Your vehicle has an oil leak.

Before you panic, it’s important to realize that even meticulously maintained vehicles sometimes develop oil leaks. While a leak is never a good thing, it doesn’t necessarily spell disaster either. According to RepairPal, the issue could be something as simple as being overdue for an oil change. Plus, some cars are just more prone to oil leaks.

Having said that, it does indicate a potentially very bad situation for your car and should not be ignored. Seemingly minor leaks can quickly turn into major repairs or even engine failure.

Regardless of what you drive, discovering that your vehicle is leaking oil is always worrisome. It helps to understand what causes cars to leak and — more importantly — what you can do when it happens.

Oil filter

In most vehicles, the oil filter screws into place. Because of this, it’s relatively easy for it to become slightly loose or misaligned and begin leaking. It’s fortunately fairly simple to change your own oil filter — and oil, for that matter. Edmunds has a fantastic step-by-step tutorial that’s easy to follow.

Oil pan and gasket

The oil pan sits at the bottom of the engine and acts as a reservoir, cleaning, lubricating, and cooling the motor. Its location makes it vulnerable to damage from road debris, which can cause punctures and result in a leak. A rubber gasket seals the pan, and it can also become damaged or worn out over time, causing a leak.

Pan or gasket leaks can be challenging to identify and repair because of where they’re situated, so many people opt to have a mechanic do them.

The drain plug and the valve cover gasket

Sitting at the bottom of your car’s oil pan is the drain plug, a simple but essential part. It gets removed during oil changes, and if it is even slightly misaligned when it’s put back in, it can cause a leak. Being too loose or overtightened can also result in a leak.

A car’s valve covers keep the oil inside the engine, and they’re held in place with rubber gaskets. As the gaskets age, they wear out and become brittle, no longer able to form a proper seal and thus resulting in leaking. Some cars are notorious for having problems with faulty valve cover gaskets, but you can slow or prevent major issues by having your oil changed regularly.

The filler cap

The oil filler cap is perhaps the most basic component in your car’s engine — but arguably one of the most important. It’s the simple cap that gets removed when oil is added to the engine. If the seal gets worn out or the cap is loose, damaged, or missing, it causes a substantial leak. Take care to replace this carefully after checking or changing your oil, and get a new cap immediately if you notice it’s broken or worn.

Check your oil frequently

It’s important to note that not all oil leaks are visible. For that reason, it’s crucial to check your vehicle often so you know how much it’s losing. To properly check it, make sure the engine is cold and pull out the dipstick, then insert it again. If your oil level is between half and full, your vehicle is sufficiently full. If it’s less than half full, it needs to be topped off.

While your car is still leaking, whether visibly or not, check the oil frequently. Bring it into a professional mechanic if the level consistently drops as this may indicate a serious problem.