It’s a beautiful morning. You wake up early, have breakfast, and are ready to head to work. But as you pull out of your driveway, you notice an unsightly oil stain. Oh no! While it may seem like a minor inconvenience, an oil leak should not be taken lightly. Your car needs oil to function properly, so it’s crucial to understand why your car is leaking oil when parked and what actions you should take.
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The Common Culprits of Oil Leaks
If you’ve ever dealt with a car that burns oil, you know how tricky it can be. Sometimes, though, the oil loss isn’t discreet. It presents itself as a dark stain on your driveway. Before you consider degreasing and pressure washing the stain away, let’s explore the possible causes of the leak:
1. Faulty Gaskets or Seals
Worn-out gaskets and seals are often the primary culprits behind oil leaks. These components endure extreme heat and pressure every time you drive. While some seals are challenging to access and require professional assistance, there are three common gaskets to examine:
- The Oil Pan Gasket seals the oil pan to the bottom of the crankcase.
- The Oil Pan Drain Plug facilitates oil drainage. A loose drain plug or a failed gasket can result in a leak.
- The Valve Cover Gasket(s) seals the valve cover to your engine’s head. This gasket can be found in your engine bay, often near the top of the engine. A leaky valve cover may emit a burning oil smell as oil drips onto the exhaust manifold.
2. Damaged Oil Filler Cap
The oil filler cap, usually located on the top or side of your engine, can also be a source of oil leaks. If the cap’s threads or o-rings are damaged, you may notice oil on belts and other engine components.
3. Damaged Oil Pan or Oil Filter
If your vehicle rides close to the ground, a damaged oil pan or oil filter could be the culprit, especially if you recently scraped the bottom of your car on a speed bump or sidewalk. Damage to the oil pan can cause cracks in aluminum pans or holes in steel pans, resulting in oil leaks. Additionally, if you spot a substantial oil puddle under your car, it’s possible that the oil pan or oil filter has been punctured or cracked.
4. Bad Rear Main Seal
If all else seems fine, your leak may originate from a crucial seal, such as the rear main seal. This seal prevents oil from leaking out of the rear part of your engine, where it connects to the transmission. Depending on the severity of the failure, you may notice small drips when the car is off and larger puddles when it is parked but still running. This occurs because the vehicle’s oil level sits lower than the rear main seal when the engine is turned off. When the engine is running, oil circulates throughout, becoming less viscous and capable of slipping past the rear main seal into the transmission bellhousing. The accumulated oil then drips out when the car is parked.
As tempting as it may be to top off your oil and continue driving, it’s essential to replace worn-out rear main seals promptly. They can experience total failure and rapidly leak oil. Since the repair usually involves removing the transmission, it’s best to leave it to the professionals at Firestone Complete Auto Care.
How to Address Oil Leaks
Finding the source of an oil leak can be messy and time-consuming. But fear not! The experts at Firestone Complete Auto Care have the knowledge and experience to get you back on the road. Their full-service oil changes include a comprehensive 19-point inspection, ensuring that any leaks are identified and resolved. Moreover, they can help you stay on top of scheduled maintenance to prevent future leaks.
Drive and park with confidence by scheduling an appointment at your local Firestone Complete Auto Care today!