What Is Transmission Fluid?

Automotive Blog

Your transmission is one of the most important--and expensive--parts in your car. The transmission fluid helps this critical piece of your car continue to function properly. Knowing about the transmission fluid and your role in maintaining it can help you take better care of your car.

What is transmission fluid?

Transmission fluid is the lubricant that helps the interior parts of the transmission moving smoothly during operation.

How often does it need to be replaced?

This depends on the type of car you own. 100,000 miles is typical. Check your car's owner's manual for a definitive answer, but note that some mechanics may recommend changing your fluid more often than the manufacturer recommendations.

Can you check whether or not your transmission fluid is dirty?

Yes. First, you'll need to locate the dipstick. The location of the dipstick depends on the car, so check with your owner's manual to determine the precise location. Check your transmission fluid when the engine is warm, turned on and in park or neutral gear. Here's how:

  1. Pull out the dipstick.
  2. Dip your finger into the fluid at the end of the stick. It should be a clear pink color.
  3. Rub the fluid between your fingers. You should feel no grime and should smell no burnt odors.

As it ages, the transmission fluid becomes a dark brown in color and develops flecks of grime. The burned smell is either an indication the transmission fluid has been used up, but it could also be an indication of mechanical problems in your transmission.

If your transmission fluid is darker than pink, does that automatically mean it should be replaced?

Transmission fluid doesn't change from pink to dark brown overnight: there are degrees. This means that fluid that's somewhat darker than pink may not need to be replaced urgently. If you're not sure, check your owner's manual for the recommended number of miles before fluid needs to be changed, and check with your car's service records to see when it was last replaced. If you still have several thousand miles to go, then you probably don't need to bring it in right away.

Note that city driving, cargo hauling, mountain driving and other stop-and-go driving conditions can cause the early deterioration of transmission fluid, and may necessitate fluid changes more often.

What happens if you don't have a mechanic replace your transmission fluid when it's dirty?

The transmission fluid helps your transmission change gears smoothly. Driving with dirty fluid can cause your transmission to become damaged and over time can lead to mechanical failure.

For more information about transmission fluid, speak with your mechanic. To learn more, speak with someone like Advanced Auto Care.


16 November 2015