Click to Print
. . . . . . .
Thursday, June 5,2014

How Often Should You Change Your Car´s Transmission Fluid

By Teresa Aquila  

Good question. How often should you change your transmission fluid and how important is this routine maintenance? Yes I said routine.

Transmissions are the driving force behind making your vehicle travel down the road, and neglecting it can put your wallet in a tail spin. Transmissions are made up of clutches, discs, solenoids (in today’s automobiles) and a filter. Neglecting it not only will send you looking for alternate transportation in the short term, but the costly repair bills could cause a phone call to your credit card lender. All of this can be avoided by simple routine maintenance.

I am an advocate of Preventative Maintenance and it has been a large part of my mechanical career in just about every position I have held working as a mechanic at various employ- ers, including my own business. Let’s talk about the makeup of the transmission, no not the kind we put on our faces, but the nuts and bolts of it. Automatic transmissions are made up of Clutch plates, discs, hydraulic fluid (automatic transmission Fluid ATF) and a filter. Newer vehicles are manufactured with electronic solenoids which are operated by your cars computer system. They operate the shifting portions in the transmission. Transmission fluid is like engine oil, if it is not changed during its regular maintenance intervals, in time it loses its ability to lubricate and create friction. When the lubrication has dimin- ished, the clutch plates and discs begin to wear prematurely causing it to fail.

Once it begins down the road of fail- ure, there is no saving it other than a costly rebuilding. For my customers, keeping them traveling down the road and less time in my shop is the key to happy customers.

When should I change my transmis- sion fluid:

Check your owner’s manual you know the book that never seems to make it out of the glove compartment for the service intervals or by asking your mechanic. Many manufactures recommend 30,000 miles, others refer- ence longer periods. If you own a vehicle with over 150,000 miles, I would recommend replacing it a little sooner. Recently a friend contacted me with some power issues on his 1998 Camry and possibly suspected the transmission. My first question to him was, when did you change your transmission fluid last? With the extent of silence on the phone, which I think he was trying to think back, the answer was, I have no idea. Right then and there I knew it at least needed to be inspected. He brought over the Camry and I pulled the transmission dip stick, here is what I saw.

The red arrow indicates what the fluid looked like when I pulled out the dip stick to check the fluid color and level. As you can see it is very dark in color indicating that the transmission fluid has lost its ability to perform properly and the fluid it burnt. The purple arrow indicates what the color of the transmission fluid should look like. I immediately placed the vehicle on the lift and removed the old fluid, removed the pan to check for metal fragments. This will be signs of transmission failure. In this case, there were no fragments present. I replaced the filter, removed all of the old transmission fluid left in the transmission, reinstalled the pan and added new pink fluid. Taking it out for a spin will be the test of time to see if any harm was done. Many times when you service the transmission after the fluid has lost it capabilities, it could fail. It is always a crap shoot at this point. I instructed my friend to drive the vehicle and I guarantee if any damage was done, it will not be long before it will leave you stranded.

The moral to this story is, remember to always perform the required routine maintenance on all your vehicles and they will give you miles of driving pleasure. Happy Motoring.


  • Currently 3.5/5 Stars.
  • 1
  • 2
  • 3
  • 4
  • 5