ATF change interval in a Saab 9-5

[oravla]

Hi there!

I've a 2004 Saab 9-5 that comes with the Aisin transmission and it uses the toyota t-iv ATF.
I changed the fluid for the first time at 50k miles. It came out pretty dark, but without a burn smell. I changed it again at 62k miles and it was also dark, with a redish dark brown color.
I was planning in changing the fluid every 25k miles, but after seeing how the fluid came out in my second change, I'm considering now changing it every 12k miles until I see a cleaner looking fluid coming out.

Considering that every change renews around half the fluid in the gearbox, what would you do?

Thanks in advance

 

[KrisZ]

If you did just a drain & fill, then 12k intervals sound ok. For full fluid exchanges, like via cooler lines, 30k is always a safe interval.

Regarding ATF color, I would not worry about it much, if the transmission is shifting normally and the fluid doesn't smell burned.
My Mazda 3 is the same way in that regard, while the fluid stays nice and red on the dipstick, when drained it is dark and not transparent (due to clutch material I guess), I never noticed shifting problems, so it's the nature of the beast I guess

 

[oravla]

Now that you say that, it makes sense. I've also found that the fluid in the dipstick looks normal, just before I drain it. Maybe is just the way it works.
I'll try 25k miles for the next drain and see how it goes. It's not that long of interval either.

 

[Dick in Falls Church]

Do yourself a favor and do a drain/refill every 12-15,000 miles if using a non-synthetic ATF. Should be able to at least double the interval if you use synthetic (assuming that you've done several drain/refill operations when first going to synthetic).