I have a 2005 Mazda 6 6s 3.0 fluid has never been changed @ 135,000 mi. No tranny issues at all...

But you hear all the myths about NEVER do it if you have gone this long...Just looking for some experienced advice. On this particular car, would I be safe to a tranny fluid change service?

Advise

 

All I can tell you is I have with no problems.

 

So were you in the same boat doing it at high-mileage after 100K?

 

I have a 96 lumina I bought used, changed it over 100K. I am unsure if it had been serviced prior, but I doubt it was. What condition is your fluid?

 

It is dark...like black... It needs a change..

 

I'd drain it, refill it, drive 100 miles, drain it, and refill it.

 

Correction...Tanny shop says it is brown not black...but I will do so. I was wondering on what internal or how I should do this... I assume with the drain plug I will only get about 3-4 qts out...my assumption

 

Not sure exactly how much you'll get out, but this is why you do it a few times as stated by Kevinkpk.
The only way you'll bet it all out is a flush and fill as some fluid will be in the torque converter. The flushing may cause more damage than good.
If at all possible it would be good to remove bottom pan if possible and cleaning that, inspecting it for bits.

 

There is no drain plug on the transaxle. watch some youtubes on this topic.

 

Seriously....I assumed there would be...so how does a newbie go about this?