I have a 2010 Mazda 3 Sport 2.5L. I have been doing a lot of reading on here from threads that were 5+ years old on the matter. Of course there is always the 2 beliefs of whether or not to change the transmission fluid. The car was bought brand new by my father in law for my wife, he has since passed away and I cannot ask him all the maintenance that was done (although I know he kept on it all). Recently, I have flushed out and changed the brake fluid (it was dirty as heck) and flushed and replaced the coolant. I checked the transmission fluid and it is not a slight of pink at all, it is a dark brown color. I am debating on whether or not to change the fluid, and how to go about doing it.

I was at first thinking of draining and refilling (most people say they get about 3 qts out from drain at the pan), then driving for 10 min or so. Then doing another drain and and refill. And then finally drain, drop the pan, replace filter, and then refill again. The car just turned 120,000 miles and it is an automatic transmission.

Appreciate your thoughts. Also, I was looking at where to get a new gasket and filter and stumbled upon 2 places, will the one from autozone work fine?

Duralast Transmission Filter (A/T) TF410 - Read Reviews on Duralast #TF410

https://www.partsgeek.com/catalog/20...ilter_kit.html