Atf

mazda
mazda3
transmissions

#1

I recently took my car in to get a part from the dealer and they did a quick inspection. They said that the ATF was “dark” and needed to be replaced soon, but my car has only 25K miles! Is this a bad sign, or is it normal? Should I get a flush done soon? Maybe at 30K miles? Thanks for your help!


#2

I think replacing ATF every 30K miles is an excellent idea. Yes, dark colored ATF is a bad sign. However, dealers are known to try to sell you something every time you come in. Did you see the fluid for yourself? If not I suggest you check it out and see if it really is dark.

But have it changed at 30K regardless.


#3

Dark transmission fluid is never good, but if you’re not having any other problems, all you can really do at this point is to replace it and see what happens from here on.

Since the car is presumably still under warranty, make sure this information about the fluid is put into your service history. Some may disagree, but I’d stick with the dealer for the fluid change and any future transmission-related work, so that if the transmission does fail outside the warranty, you have the best chance of some goodwill help on the repair.


#4

I agree and would add one thing…NEVER FLUSH a transmission. Have the fluid drained and a new filter installed if it has one.


#5

I second that…Make sure they DO NOT FLUSH the transmission. Ask them to just “remove the transmission fluid pan and clean it, replace filter, and change the fluid”. That’s all your automatic tranny needs every 30k miles.


#6

Darkening ATF is not necessarily a bad thing. SMELLING BURNT is. Over the last decade discoloration is not the demon it used to be when TYPE F and DEXRON (I …but it was “just Dexron”) ruled.

Keep in mind that most of us are geezers and learned stuff in the 70’s and think that time stays frozen.

Fluid exchanges are just fine. They do absolutely NOTHING harmful. Add no chemicals. They just swap the old fluid out for new. The only side effect would be if your trans was sophisticated and had adjusted to sheared ATF (many shear from a 10 weight to a 5 weight quickly) and would need time to adjust the pressures of the newer fluid.

For the money the dealer will charge you for a pan drop, someone with a T-Tech will exchange the fluid. I’d do it myself via the cooler lines.

Get a synthetic fluid like Amsoil or Mobil 1 if you need some peace of mind factor.


#7

Great advice! Thanks to all the responses. It seems to me that it is a bad idea to get the transmission flush done. I have read elsewhere that it can make things worse. I will be interested to find out how much it will cost to replace the fluid and filter instead of a transmission flush. Considering, I don’t have the know-how to change it myself.


#8

I would advise you not do it yourself. Remember too that drain and refill does not replace all the fluid like a motor oil change, which in my opinion makes it more critical to do on a regular schedule…and 30-40K has served most well. The cost for me has always been in the range of coolant change service and may be for you.