My method on my cars has been complete ATF flush every 30K, but the manual for my '14 Stang has some crazy high mileage before its recommended, along with differential fluid. What is common practice out there?

 

Every good transmission person I talked to said never flush a trans.. I do it the old fashion way..
I do it around 30k for the first then every 60 to 80k after. Suburban is turning 315,000 soon. No problems.

 

What's the old fashioned way - drop the pan? Pretty sure there isn't a pan to drop on these cars.

 

I think this is how you do it.

http://www.mustangevolution.com/forum/f356/t374210/

 

If you have a good relationship with your local Ford dealer like I do, let them do it. I watched them do mine, it cost $200 for the filter and fluid. They dropped the pan and changed the filter. I got to see it before they cleaned the pan. Had a little black crap in it. After they changed the filter and put the pan back together, they did a 'low pressure' flush to fill the transmission back up until clean fluid was flowing out of the torque converter. I had this done with 20,000 miles on my 2011 v6 Mustang 2 years ago. I now have 27,000 miles . The service manager told me the next time they won't have to drop the pan and just do a low pressure flush. I over kill all my fluids

 

Well, I stand corrected. Didn't realize it was like that - lots of modern automatics don't have that option, if memory serves.