2015 BMW 640i XDrive Is Leaking Oil

Discovering the Causes of Oil Leaks in Your 2015 BMW 640i xDrive and How to Address Them Effectively

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Reviewed by
Devin Cabugcal
Written by RepairPal Car Genius
Updated January 14, 2025
0%
80% chance it's the
Oil System Components
0%
20% chance it's the
Engine Gaskets
The most common reasons a 2015 BMW 640i xDrive is leaking oil are oil system component failure and leaking engine gaskets.
  • Oil System Components: A failure in oil system components, such as a worn oil pump or clogged oil filter, can lead to inadequate lubrication and potential engine damage.
  • Engine Gaskets: A worn or damaged engine gasket can lead to oil or coolant leaks, resulting in engine overheating or loss of lubrication.
Proper diagnosis will determine the exact cause of your symptom, saving you money on unnecessary repairs. The diagnostic experts at RepairPal Certified shops have the right tools and experience to solve any symptom.

How much does it cost to fix a 2015 BMW 640i xDrive is leaking oil?

Common Repairs

The total repair cost will vary based on the condition of your vehicle and the number of repairs needed to fix your symptom. Proper diagnosis will save you money by finding the exact repairs needed to fix your car right the first time.

Oil pans don't wear out or break like other parts, they generally only need to be replaced because of external damage from an accident or an improperly tightened drain plug. The main symptom you will experience is an oil leak underneath the engine of your car. The oil that leaks from a damaged oil pan will range from dark brown to dark black. If the leak is large enough or occurs for long enough the oil level will be low enough to turn the oil pressure or low oil level warning light on.

An oil leak may be noted on the ground where the vehicle is parked. However, many vehicles have plastic trays underneath the engine that may catch leaking oil and conceal the leak. In such cases, a low oil level, a burning oil smell, or even smoke from oil burning in the engine bay may be noted.

»MORE: Signs of a bad oil pan gasket

A bad oil level sensor may cause a false reading of the engine oil level. The oil level warning light may illuminate even when the oil level (checked manually) is within an acceptable range. The warning light may also come on and off intermittently if the sensor is faulty. An error code may be sent to the PCM and a check engine light may come on the dashboard as well if the sensor is bad.

The engine oil pressure warning light will come on if the engine oil pressure is low, or if the oil pressure sensor is faulty. In either case, engine power may be reduced significantly. The check engine light may also illuminate, and an on-board diagnostic (OBD) trouble code will be stored in the vehicle's computer.

What steps should I take to diagnose the oil leak in my 2015 BMW 640i xDrive?

When diagnosing an oil leak in your 2015 BMW 640i xDrive, it's crucial to follow a methodical approach that begins with the most straightforward assessments. Start by pinpointing the leak's source, focusing on common areas such as the valve cover gasket, timing cover gasket, and oil filter housing. Regularly checking your oil levels can provide immediate clues; a significant drop may indicate a leak. Look for visual signs like oil stains on your driveway or pools of oil beneath your vehicle, which can help you identify the leak's location. Additionally, be alert for any unusual smells or smoke from the engine, as these could indicate a more severe issue. After gathering this information, inspect the identified areas for visible oil seepage and assess the condition of seals and gaskets, as these are often the primary culprits behind leaks. By following this structured diagnostic process, you can effectively identify and address the oil leak, helping to maintain your BMW's performance and longevity.

What are the common causes of oil leaks in a 2015 BMW 640i xDrive?

When dealing with oil leaks in a 2015 BMW 640i xDrive, it's crucial to understand the common culprits that may be contributing to the problem. One of the primary sources of leaks is the valve cover gasket, which can wear out over time and lead to oil seeping out. Similarly, the oil filter housing gasket is another frequent offender, often deteriorating and allowing oil to escape. Additionally, the oil pan gasket can also fail, especially in older vehicles, resulting in noticeable leaks. As the car ages, the deterioration of various engine gaskets and seals can further exacerbate the issue, making it essential to regularly inspect these components. Moreover, driving on rough terrain can accelerate the degradation of these gaskets, leading to leaks. If you notice signs such as a burning oil smell, oil stains on the ground, or a drop in oil levels, it’s advisable to investigate these areas promptly to prevent potential engine damage and maintain the performance of your BMW.

How urgent is it to address the oil leak in my 2015 BMW 640i xDrive?

Addressing an oil leak in your 2015 BMW 640i xDrive is not just a matter of convenience; it is a critical maintenance task that demands immediate attention. Ignoring an oil leak can lead to severe consequences, including diminished engine performance and increased risk of overheating, which can ultimately result in catastrophic engine failure. The longer you wait to identify and fix the source of the leak, the more extensive the damage can become, leading to significantly higher repair costs down the line. Moreover, an oil leak can compromise the safety and reliability of your vehicle, making it essential to act swiftly. By prioritizing the repair of an oil leak, you not only safeguard your engine's health but also ensure the longevity and optimal performance of your BMW 640i xDrive. Therefore, if you notice any signs of an oil leak, it is crucial to investigate and address the issue promptly to avoid further complications.

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