Skip the auto shop - Our mechanics make house calls

Q: What Does Transmission Fluid Do?

asked by on

What Does Transmission Fluid Do?

Modern automatic transmission fluid (ATF) typically contains a wide variety of chemical compounds intended to provide the required properties of a particular ATF specification depending on the manufacturer.

Most ATFs contain some combination of additives that are required for there lubricating qualities,such as anti-wear additives, rust and corrosion inhibitors, detergents, dispersants and surfactants, which protect and clean metal surfaces kinematic viscosity and viscosity index improvers and modifiers, so your transmission fluid does not gel up or solidify in the winter. It also helps to seal by adding swelling additives and agents (which extend the rotational speed range and temperature range of the additives).

It also has anti-foam additives and anti-oxidation compounds to inhibit oxidation, as well as gasket conditioners and petroleum dye. All ATFs contain friction modifiers, except for those ATFs specified for some manufacturers transmissions that specifically exclude the addition of friction modifiers such as tractors and off-road vehicles.

There are many specifications for ATF, such as the Dexron and Mercon types (G.M. and Ford), which the vehicle manufacturer will tell you what the ATF specification appropriate for each vehicle. The vehicle’s owner’s manual will typically list the ATF specifications that are recommended by the manufacturer. The transmission dipstick will also have the fluid type imprinted on it if you do not have the owner’s manual.

The owners manual will also tell you when to change the fluid, it is very important to maintain the transmission the same way you would change your engine oil. Automatic transmission fluids have many performance-enhancing chemicals added to them to meet the demands of each transmission, no matter what you drive. So you cannot mix fluid types, no matter what the circumstances are.

If for some reason you have mixed the fluid types then get the transmission serviced right away to avoid costly repairs. Different manufacturers use different chemicals to meet the same performance specifications and ATF requirements. Always check your owner’s manual for this information. If you need assistance with this, have a certified technician help you with the transmission fluid change at your own convenience.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. What Does Transmission Fluid Do?

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: clutch slave cylinder goes out and car is towed

When problems like these arise, one can look to the aftermarket world for solutions. With some research, you may be able to find a part made by a company that specializes in these vehicles and creates upgraded parts for higher...

Q: New power steering pump makes noise - 2002 Mercedes Benz CL600

Hello. From the symptoms you describe, it would appear that you have some sort of power steering fluid leak. If the fluid leaked out in less than a day, then it could even be a large leak. The power steering...

Q: Hi I had a friend replace my motor mounts on my 2004 Pacifica v-6. Apparently getting them in and out were difficult.

Hi there. The leaks from the transmission could have came from the oil pan. When using a jack to lift up the engine, if the jack was sitting on the transmission oil pan, it probably cracked the pan, or the...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...