Accidentally drained transmission overflow plug instead of oil drain plug
 

I accidentally drained transmission overflow plug instead of oil drain plug doing my first oil change on my 2005 mazda rx8 auto transmission and about id say 3 quarts of fluid came out am I good to just fill the transmission fluid back up or do I need to do a full transmission fluid change
https://cimg4.ibsrv.net/gimg/www.rx8...77a6d7adde.jpg

Edit: See below.

Since it's an overflow transmission, the trans fluid will require being at a specified temperature range for proper level setting. You will need to know the temperature range and the car will have to be level, on a lift with a scan tool hooked up monitoring live engine and trans data. You will add fluid, preferably a small amount over what you perceived came out. Run the engine at idle while monitoring live data and when the trans fluid temperature reaches the specified temperature range, you will remove the overflow drain plug. The fluid should come out in a steady stream. When it reaches a trickle or a drip while still within the specified temperature range, you can reinstall the overflow drain plug and clean the trans fluid off the pan and go drive the car to make sure the trans shifts properly.

If no fluid comes out when you remove the overflow drain plug, add more until the fluid comes out and is a steady trickle or drip. Just make sure you monitor the transmission fluid temp. Adding or subtracting fluid when the fluid is not within the specified range will leave the level set improperly.

Dont know what plug this is
 

https://cimg1.ibsrv.net/gimg/www.rx8...8310826b0d.jpg
After looking more into It I dont think this is the overflow plug and I cant find anything saying what the plug is would you happen to know what this plug drains

If you were to move your camera to the opposite angle, is that a banjo bolt? Looks like that black line is headed straight for it.

that is what it is what fluid did I drain the because thats the bolt for sure that I removed

I'm sure it was transmission fluid. More a question of how much since that's not how you're supposed to remove the fluid. Typically with automatics, you remove the entire sump pan and replace the filter while you're at it. I'm not sure I've ever even seen an automatic RX-8 in person, let alone messed around with the business end of the transmission on one, so I can't tell you anything about that particular banjo bolt. I'm not even sure I could look it up in the shop manual, because I only have the S2 set, and I don't think they're the same transmission. If you were local, I'd happily offer to poke at it with you, but someone with automatic S1 RX-8 experience is going to have to chime in to tell you anything concrete.

Thanks I was going crazy trying to figure out what plug that was I live in Pilsen Chicago IL but what are the chances youre local lol I should be fine thought I think im gonna just refill the atf through the dipstick a quart at a time running it then checking the level.

That's probably what I'd do. I'm more than a 1000 miles away, so unless someone else chimes in, you're on your own for this one. One banana. You got it.

I think that big bolt is the transmission cooler line that goes to the radiator. You may need to replace the crush washers it uses.