2005 Mazda 3



January, 13, 2013 AT 7:49 PM

Overfilled oil tank, drained transmission fluid. What do?

I had decided it may be a good idea to learn how my car works, so I really know what I'm driving, rather than just driving. I decided to go with the first thing anyone could think of: an oil change. I went out, found the proper oil, proper filter, etc. However, after getting all the supplies, instead of locating the drain for the oil, I found the one for the transmission fluid. I drained about 4 quarts of the stuff out (still thinking it was oil) and then proceeded to replace the filter, add new oil, etc. By the time I had realized what I had done, it was too late. The transmission fluid previously in the car had already been disposed of. For a while, I had thought I had overfilled the oil. So, I did what I had researched, and drained about another quart out of what I still thought was the oil. By the time I had realized that the fluid was too red to be oil, it was too late. So, basically my car is dead where it stands until further notice. I've recently located the ATF dipstick (what I presume to be it) and the transmission fill cap. Likewise, I've now located the real oil drain. As of currently, I have a mix of conventional and synthetic oils in my engine. About 8 quarts or so. The Mazda is a 2.0 liter engine, and only requires 4.5 quarts of oil. So, it's double the normal amount. Should the oil be completely drained and the filter replaced? Likewise, how do I go about replacing the transmission fluid? Or, would it just be a better idea to take it to the shop and have them do their thing?

In the words of Gob from Arrested Development: "I've made a huge mistake."


3 Answers



January, 13, 2013 AT 8:04 PM

Drain all the oil out and change the filter again. Add the necessary oil and thats that.

You never added oil to the trans? Is that correct?

Add 4 qts to the trans and run the motor and re check. If you did add oil to the trans, you need to have the system flushed out and new fluid added.

I dont think you damaged anything. Just learned a good lesson here.




January, 13, 2013 AT 8:17 PM

Didn't add oil to the trans, thankfully. The two caps are on opposite sides of the car and properly labeled. Oil was added to the oil. Transmission was just drained a bit, that's all.

Likewise, would I need to drain the rest of the trans fluid and refill it with new fluid so I could get a clean run with that? Or would that be unnecessary work?



January, 17, 2013 AT 11:05 PM

Nope, just add the trans fluid and you are good


Please login or register to post a reply.

Transmission Service Toyota Tacoma
Automatic Transmission Service
Transmission Fluid Replacement Mercedes Benz
Transmission Service Ford Super Duty F-250
Transmission Drain and Refill Kia Sportage
Code Read Retrieval/Clear Chevrolet Camaro