Oil leaks are something you cannot afford to ignore.

It doesn’t always take a trained mechanic to figure out what causes engine oil leaks.

A little hunting can reveal a lot, just don’t put it off or it can cause damage to your engine.

One of the most common reasons is due to a lack of regular oil changes. Skipping oil changes or waiting too long between intervals can cause the oil to become dirty, which can erode engine components, such as oil seals and valve gaskets.

Oil Leaks
Oil Leaks

Common Causes

  • Oil Filter

Oil filters wear out, can be aligned improperly or be loose.  Some vehicle models have additional parts in the filtration system, at the filter, that can leak. Whether you do it yourself, or it’s done by a mechanic, the filter should be changed every time you change the oil and should be checked for proper fitting.

  • The Oil Drain Plug

At the base of the oil pan is a drain plug, accessible from the underside of your car.  Worn out thread, misaligned threads, or a loose oil drain plug can be a common oil leak cause.  It’s easy to spot as there would be fresh oil around the plug, and on the side of it where it drips down.

  • The Oil Filler Cap

Oil doesn’t just drip down.  If your filler cap, covering where you put oil into the engine, is missing, loose or broken then the pressure of the engine could cause oil to spill out when the vehicle is running.

  • Valve Cover Gasket

The gasket is probably the most common cause of oil leaks, especially in older vehicles or vehicles that are used frequently & have a high number of miles.  The gasket is a seal that joins the head two metal parts of the engine, such as the between the block and the head(s) as well as the engine block and the oil pan.  Over time, and with a buildup of sludge (oil that breaks down over time due to prolonged temperature exposure), the pressure increases which can cause leaks and failures in the seal of the gaskets.

Sometimes damage to the oil pan on the underside can cause minor to severe leaks.  This occurs when running over road debris, large rocks if traveling off-road, and even accidentally hitting an animal while traveling.  Any of these can dent the oil pan and compromise the seal or oil drain plug.

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A leak of any kind should be addressed immediately, but an engine oil leak even more so. Knowing what causes engine oil leaks will help you know where to look and how to start fixing it yourself. Don’t ignore it, or hope it fixes itself. Be proactive. Protect and preserve your vehicles performance so you can keep it on the road where it’s meant to be.