BMW E39 Automatic Transmission Fluid Type Guide

Understanding Automatic Transmission Fluid for Your BMW E39

When it comes to maintaining your BMW E39, one of the most crucial aspects is ensuring that the automatic transmission fluid (ATF) is the right type. Using the correct fluid not only keeps your transmission running smoothly but also extends its lifespan. So, what exactly should you be using?

Manufacturer Recommendations

BMW has specific recommendations for the type of automatic transmission fluid suitable for the E39 models, particularly those equipped with the 5-speed automatic transmission (A5S 325Z). The recommended fluid is typically:

– BMW ATF (Automatic Transmission Fluid)**
– Specification: Dexron III or Mercon V**

These specifications are crucial because they ensure that the fluid has the right viscosity and additives to protect the internal components of your transmission.

Why These Specifications Matter

Using the correct ATF is not just a matter of preference; it’s about performance and longevity. Here’s why adhering to these specifications is important:

• Viscosity: The fluid must have the right thickness to provide adequate lubrication and cooling. If the fluid is too thin, it won’t protect the gears properly. If it’s too thick, it can cause shifting issues.


• Additive Package: The additives in the fluid help to prevent wear, reduce friction, and keep the transmission clean. Using a fluid that doesn’t meet BMW’s specifications can lead to premature wear and potential failure.


• Heat Resistance: Automatic transmissions generate a lot of heat, and the fluid needs to withstand high temperatures without breaking down. The recommended fluids are designed to handle these conditions effectively.

Fluid Types and Their Characteristics

There are various types of ATF available in the market, but not all are suitable for your BMW E39. Here’s a breakdown of the commonly recommended types:

1. BMW ATF: This is the OEM fluid specifically formulated for BMW transmissions. It provides optimal performance and protection.


2. Dexron III: A widely used fluid that meets the specifications for many GM vehicles, it is also compatible with BMW transmissions. However, always check compatibility with your specific model.


3. Mercon V: This fluid is designed for Ford vehicles but is also compatible with BMW transmissions. It offers good performance but may not have the same level of protection as BMW ATF.

Where to Find the Right Fluid

You can purchase the recommended automatic transmission fluid from various sources:

• BMW Dealerships: The safest option is to buy directly from a BMW dealership. They will have the OEM fluid that meets all specifications.


• Auto Parts Stores: Many stores carry Dexron III and Mercon V fluids. Just make sure to check the labels for compatibility with your E39.


• Online Retailers: Websites like Amazon or specialized automotive sites often have a range of ATF options. Again, ensure you verify the specifications before purchasing.

By sticking to the manufacturer’s recommendations and using the correct type of automatic transmission fluid, you can help ensure that your BMW E39 runs smoothly and efficiently for years to come.

Recommended Oil Brands for Your BMW E39 Transmission

When it comes to maintaining your BMW E39, choosing the right automatic transmission fluid is essential. Many owners have shared their experiences on forums and in discussions, providing valuable insights into which brands perform best. Here’s a rundown of some of the most recommended oil brands for your BMW E39 automatic transmission fluid.

OEM Options

While there are many aftermarket options available, several BMW owners prefer to stick with OEM fluids. Here are the top recommendations:

1. BMW Genuine ATF: The go-to choice for many E39 owners, this fluid is specifically formulated for BMW transmissions. It meets all the necessary specifications and provides optimal performance.


2. Liqui Moly ATF: Known for its high-quality formulations, Liqui Moly offers an ATF that meets BMW specifications. Many users report smoother shifting and better overall performance when using this brand.

Aftermarket Brands

If you’re looking for alternatives, several aftermarket brands have garnered positive feedback from BMW E39 owners. Here are some of the most frequently mentioned:

1. Valvoline MaxLife ATF: This fluid is compatible with multiple specifications, including Dexron III and Mercon V. Many owners have praised its performance, especially in older transmissions, where it helps reduce slipping and improve shifting quality.


2. Castrol Transmax Import: Designed for import vehicles, this ATF is well-regarded among BMW enthusiasts. Users have reported that it provides excellent protection and performance, particularly in high-mileage vehicles.


3. Royal Purple Max ATF: Known for its synthetic formulation, Royal Purple is often recommended for those looking to enhance performance. Owners have noted improved responsiveness and smoother shifts when using this fluid.

Owner Experiences and Feedback

Many BMW E39 owners have shared their experiences on various forums, discussing the pros and cons of different transmission fluids. Here are some key takeaways:

• Several owners have reported that sticking with OEM fluids, like BMW Genuine ATF, often results in fewer issues down the line. They emphasize that while it may be more expensive, the peace of mind is worth it.


• Some users have had great success with Liqui Moly, stating that it not only meets specifications but also seems to improve shifting performance, especially in colder weather.


• Valvoline MaxLife has received mixed reviews. While some owners appreciate its affordability and compatibility, others have experienced issues with shifting after using it. It’s often recommended for those on a budget.


• Castrol Transmax Import has been praised for its ability to maintain performance in high-mileage vehicles. Owners have noted that it helps reduce transmission noise and improves overall drivability.


• Royal Purple Max ATF is often highlighted for its synthetic properties, which many users believe offer better protection and performance. However, it tends to be on the pricier side, which may deter some owners.

Where to Buy

Finding the right transmission fluid for your BMW E39 is easier than ever. Here are some common places where owners have successfully purchased their recommended oils:

• Local Auto Parts Stores: Chains like AutoZone, O’Reilly Auto Parts, and NAPA often carry a selection of both OEM and aftermarket fluids.


• Online Retailers: Websites like Amazon, RockAuto, and even specialized automotive sites often have competitive prices and a wide range of options.


• BMW Dealerships: For those who prefer OEM products, visiting a local BMW dealership is the best option. While it may be pricier, you can be assured of the quality.

With so many options available, it’s essential to consider the experiences of fellow BMW E39 owners when selecting your automatic transmission fluid. Whether you choose OEM or an aftermarket brand, ensuring compatibility and quality will help keep your transmission running smoothly.

Change Interval for Your BMW E39 Transmission Fluid

Maintaining the health of your BMW E39’s automatic transmission is crucial for its longevity and performance. One of the key aspects of this maintenance is understanding the change interval for the transmission fluid. Knowing when to change the fluid can prevent costly repairs down the line.

Recommended Change Intervals

The general consensus among BMW enthusiasts and mechanics is that the automatic transmission fluid should be changed every 30,000 to 60,000 miles (approximately 48,000 to 96,000 kilometers). However, this can vary based on driving conditions and personal driving habits. Here’s a breakdown:

1. Normal Driving Conditions: If you primarily drive in moderate conditions, a change every 60,000 miles (96,000 km) is often sufficient.


2. Severe Driving Conditions: If you frequently engage in stop-and-go traffic, tow heavy loads, or drive in extreme temperatures, consider changing the fluid every 30,000 miles (48,000 km).

Why Change Transmission Fluid?

Transmission fluid degrades over time due to heat and contamination. Here are some reasons why regular changes are essential:

• Contaminants: Over time, the fluid can accumulate dirt, metal shavings, and other contaminants that can harm the transmission.


• Heat Breakdown: High temperatures can cause the fluid to break down, losing its lubricating properties and leading to increased wear on transmission components.


• Performance Issues: Old or degraded fluid can lead to sluggish shifting, slipping, and other performance issues that can compromise your driving experience.

Partial Transmission Oil Changes

In many cases, a full transmission fluid change is not feasible without removing the transmission from the vehicle. This is where partial transmission oil changes come into play.

What is a Partial Change?

A partial transmission oil change involves draining a portion of the old fluid and replacing it with new fluid. This method is often more accessible and can be performed without the need for extensive labor.

Benefits of Partial Changes

• Cost-Effective: Partial changes are generally less expensive than a full fluid change since they require less labor and time.


• Improved Fluid Quality: Even a partial change can significantly improve the quality of the fluid in your transmission, helping to remove some contaminants and degraded fluid.


• Less Downtime: Since partial changes are quicker to perform, you can get back on the road sooner.

Statistical Support

According to various automotive studies and data from transmission specialists, regular maintenance, including fluid changes, can extend the life of a transmission significantly. For instance, a study by the Automatic Transmission Rebuilders Association (ATRA) found that vehicles that underwent regular fluid changes had a 50% lower failure rate compared to those that did not.

Additionally, many mechanics recommend that even if a full fluid change is not possible, performing partial changes every 15,000 to 20,000 miles (24,000 to 32,000 km) can help maintain the health of the transmission. This practice can help keep the fluid fresher and reduce the buildup of harmful contaminants.

By understanding the change intervals and the benefits of partial transmission oil changes, you can take proactive steps to maintain your BMW E39’s automatic transmission and ensure it continues to perform at its best.

What Color Should Transmission Fluid Be?