August 8, 2019
By Michael Belluomo, BG Technical Service ManagerRead time: 2 minutes

Automatic transmission fluid. What exactly does it do? And how long can it last? 

Automatic transmission fluid (ATF) has some unique and specific properties that make it the most complex fluid in your vehicle. 

What does automatic transmission fluid do?

  1. It’s a lubricant to cool and protect the metallic and non-metallic transmission parts.
  2. It’s a “friction control” interface between parts that need to have some contact in order to transfer energy to move your vehicle. 
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Most ATFs today are a mix of either semi-synthetic or full synthetic base oils. This gives the fluids longer life (meaning they protect the vital components in your transmission for a longer period of time). 

The performance additives are the guardians of the ATF. They protect the fluid every minute it’s in service (which is every second you’re driving). Ingredients such as corrosion and oxidation inhibitors, seal protectors, detergents, friction modifiers, and de-foaming polymers ensure that the fluid can cool, clean and protect the transmission for many thousands of miles.

How can you protect it? 

However, like all lubricants, the base oils and performance additives in ATF will eventually start to degrade and performance may slip (figuratively and literally). Before that happens, add a conditioner to your automatic transmission fluid. A quality ATF conditioner like BG ATC Plus® can rejuvenate and replenish vital ingredients in the ATF. This helps maintain peak performance and function.   

I recently received this question:

Can you tell me if and how often I can add your ATC product to my transmission fluid? 

Adding BG ATC Plus® keeps seals firm and pliable, smoothes shifting, and ensures the fluid is protected against deterioration from heat and wear. Use this conditioner each time new transmission fluid is installed, or once every 30,000 miles. It may also be used as a “one-time” treatment if a majority of the fluid is partially drained for repair or replacement.   

As the most complex fluid in your transmission, it’s important that this fluid lasts as long as your transmission needs it. 

Pro Tip: One way to tell if your fluid is beginning to degrade is the appearance of wear particles. Be sure to get your transmission fluid checked for wear particles at every oil change.

If you have any more questions for me, please feel free to send them!

by Michael Belluomo
Technical Service Manager
30 years of experience in fuel and lube technologies