Auto gearbox oil changes - when do I have to change?

Both of my cars have a standard automatic gearboxes. Is there any mileage recommendation for replacement of the fluid in these transmissions. Curious as there seem to be fluid replacement problems in many auto boxes these days. They are a Honda Civic 2010 and a Suzuki Alto 2013.
The Civic has a 5-speed torque converter auto and the Alto has a 4-speed torque converter auto. It would probably benefit both to change the fluid after 5 to 6 years. Not as necessary as with a Dual Clutch transmission, a CVT, or a torque converter auto with 6 speeds or more (some now have 9).
Answered by Honest John on

Ask Honest John