How often do you guys change your transmission fluid?

Back in the day when you could get a filter and a couple gallons of Dexron III for about $25, I used to change mine every 30K. It was always beautiful red in there, and I always got 225K out of my car and sold it without ever having a problem.

I just dropped $65 on 8 qts of Dexron VI and a filter for my '08, as it requires the VI. I changed it once at 75K, and today at 150K. The stuff I drained out was more brown than red. The factory says 100K intervals for fluid changes, but I'm not even happy doing 75K. I might drop back to 50K.

What do you guys do?

In the past, 30 k miles was about right for my trans changes. I never worried about doing it too often because one only gets about 1/2 to 2/3 of the fluid out. If the fluid comes out brown, then you are still leaving bad fluid in the trans.

Yes, one can pull off a cooler line and bleed off some more bad fluid but you won't get it all.

So, best to change it a wee bit more often than needed, IMHO.

I lean towards 50K.....

I usually go about 30k regardless on every car I have owned. My comp g has a firm shift kit and line pressure increased so I change it once a year to be safe. probably a little overkill but $60-70 a year or every two years is worth it in my opinion.

Only once in 391,000 miles and it still runs good, uses a little or leaks it out, but still smooth.