A vehicle’s transmission is a complex assembly that takes the power generated by the engine and transfers it to the wheels. Your transmission selects different gears to transfer that power differently. Lower gears for more low-end torque or higher gears for higher speeds. Over time, regular use causes small particles of the transmission’s metal to wear off and integrate into the transmission fluid. Clean transmission fluid allows smooth shifting and overall transmission operation. While the shifting action itself, and the role transmission fluid plays, differs between automatic and manual transmissions, the impact of dirty transmission fluid is the same: poor performance, and increased wear on the mechanical parts, contributing to earlier transmission failure.
Routine Transmission Service:
Our team at Boston Motor Werks highly recommends regular transmission service at every second service appointment (no later than every 60,000 miles), or at any sign of transmission grinding, slippage, or fluid leak. The reasoning is simple: fluid is cheaper than metal. Replacing the transmission fluid, even “lifetime” fluid, is far more affordable cheaper than replacing or repairing your transmission (or parts thereof). Proactive maintenance will keep your BMW’s transmission performing at its best, and protect against unexpected failure.
- Draining the current transmission fluid.
- (Automatic only) Install new pan gasket and filter (if replaceable).
- Add the proper type and quantity of oil/fluid for your transmission.
- Check for leaks.
- Test drive the vehicle.
BMW Transmission Service
BMW transmissions are known for being very well built, requiring minimal maintenance for optimal performance. In recent years, BMW began using “lifetime” transmission fluid, which is supposed to be good for 100,000 miles– or the expected life of the transmission. This has reduced required transmission maintenance in late model BMWs. However, older models still require regular transmission service, and even newer models are not immune to transmission issues that require service. Even “lifetime” fluid wears down and can start to negatively influence performance starting around 80,000 miles.
Mercedes Transmission Service
Mercedes has a reputation for building snappy and responsive transmissions for high performance vehicles. Through the years their automatic transmissions have continued to improve, and experts have praised both the 722.6 from the earlier 2000s, as well as the 722.9 in more recent years. While the 722.6 is a 6 speed automatic transmission with 2 internal sensors, the 722.9 is a 7 speed automatic with 3 internal sensors. Sensors are an extremely important part of any transmission as they ensure optimal performance and help experts diagnose any issues. On the 722.9, the sensors are actually included in the valve body rather than an external module, which helps provide more accurate readings.