What Does Lifetime Transmission Fluid Really Mean?

What Does Lifetime Transmission Fluid Really Mean?

Many vehicle and transmission manufacturers commonly use marketing statements, "lifetime transmission fluid" and "sealed for life transmission" in their owner or service manuals. Consequently, many vehicle and transmission manufacturer maintenance schedules may no longer suggest a transmission fluid change interval.

The statements “Lifetime, Lifetime Fill, Fill for Life, or Sealed for Life” used by vehicle and transmission manufacturers, is typically understood to indicate the transmission fluid and transmission filter will last the lifetime of the vehicle while under warranty. However, these statements tend to create some misconceptions that may lead to neglecting the maintenance of the transmission. It may also not reflect the important need to change the transmission fluid in order to achieve long-term reliability of the vehicle's transmission well beyond the warranty period.

For example, statements like these have become common among many popular transmission manufacturers including variants of some Aisin and ZF 6 and 8-speed transmission types used by several vehicle makers such as Toyota, Audi, BMW, Land Rover, Jaguar, Chrysler, Dodge, Jeep, Ram, and others.

Most vehicle manufacturers will base the scheduled service intervals and recommended transmission fluid changes on the results of durability testing. These mechanical tests simulate vehicle wear, reliability, failure, and durability before the vehicle is released for public sale. Typically, these tests are associated with the duration of the expected warranty coverage period. In some cases, 5 years or 100,000 miles is recommended. If the transmission testing results in minimal failure rates the automatic transmission fluid may be approved by the factory as the transmissions first fill. The first fill fluid meets the manufacturer's objective and lasts the duration of the warranty with the least amount of investment. Unfortunately, this strategy may not prevent adverse transmission failures in the long term that could arise after the vehicle has passed beyond the warranty period.

It is also interesting to note what seems to be a contradiction or conflict in published information between the transmission manufacturers and the vehicle manufacturers. While the vehicle manufacturer may state the first fill fluid in the transmission is "filled for life," the transmission manufacturers may recommend the transmission fluid be changed every 50,000 miles or eight years, whichever occurs first.

Do I Need to Change "Lifetime Fill" Transmission Fluid?

Despite some automotive experts suggesting that you do not need to change the automatic transmission fluid, we feel this is poor advice. Here are a few good logical reasons why we feel that all transmission fluids should be changed regardless:

1. For example, published information by the transmission manufacturer ZF who makes the popular 8HP series 8-speed transmissions for many vehicle manufacturers recommends the transmission fluid be changed every 50,000 miles or eight years, whichever occurs first.
2. Transmissions have hundreds of moving components, such as needle bearings, pressure pumps, clutch packs, servo pistons, valves, and seals. These internal components mesh with one another, begin to wear, and create fine metallic particles which contaminate the automatic transmission fluid. Over time, the automatic transmission fluid (ATF) and paper filament transmission filter become contaminated with these particles. The ATF also experiences thousands of heat cycles and shear loads through use, resulting in the deterioration and depletion of key lubricating properties. The new transmission fluid is nearly clear in color. If you have ever seen the dark color of old transmission fluid, you will agree that it seems very logical that changing the automatic transmission fluid and filter is needed.
3. From our 30 years of hands-on automotive experience, there is no such thing as a truly "sealed for life" or "lifetime transmission fluid." Over time, all transmission fluids will eventually deteriorate, break down, and become contaminated and will need to be changed. Suppose your goal is the long-term reliability of your car or truck, and you plan to drive it for well over 100,000 miles. Experience and history have shown performing regular fluid changes is essential to minimize expensive transmission repairs and extend the life of the transmission.
4. Some dealerships recommended that you wait for the transmission to give signs of problems, then bring it in for service of the transmission. This is typically suggested to get the vehicle through its warranty duration period. If the vehicle manufacturer only says to change the fluid or remove the transmission pan if it is leaking or an issue exists with the valve body or torque converter, the damage is already done. Regular fluid and filter changes can prevent many issues with the internal transmission components. Do not wait to change the transmission fluid and filter until after the transmission gives you signs of problems. If you are experiencing a problem with the transmission such as slippage or erratic shifting, often these symptoms are caused by both dirty transmission fluid which has lost its lubrication properties and is now wearing on internal transmission components, or a dirty transmission filter is causing shifting delays or slippage. Abnormal symptoms like these can be avoided with regular transmission fluid and filter changes.
   
   Pictured Example: Transmission service performed in our repair shop on a vehicle with a 5-speed ZF Tiptronic automatic transmission with approximately 80,000 miles on it. The customer complained of shifting problems when the transmission was cold. Note the dirty metallic sediment that was removed from the transmission drain pan. After changing the automatic transmission fluid using one of our BLAU Transmission Fluid Filter Change Kits, the customer reported that his transmission shifting problems were gone.
   
   If you're experiencing transmission shifting problems with your Aisin or ZF transmission variants used by several vehicle makers such as Toyota, Audi, BMW, Land Rover, Jaguar, Chrysler, Dodge, Jeep, Ram, and others, Blauparts recommends changing your automatic transmission fluid and filter as a first step in solving the problem.