Hey scotty i got a 2012 honda civic lx with 30,000 miles on it and transmission fluid never been changed when do you think it needs to be changed?
I would just change it now for piece of mind (drain and fill along with filter change). Most other cars that get driven the US DOT-reported average of 13,500 miles a year would need their transmission fluid changed every 3-4 years (which comes to every 40,000-50,000 miles for a regular - NOT CVT - automatic transmission). At 9 years, I would change it now.
Based on age alone, I would say NOW is a good time.
40 to 50000 is a good window.
If the owners manual specifies an interval I would go by that.
What does the owner's manual say?
The manual comes less into play because most manufacturers don't account for a vehicle being nearly 10 years old and ONLY having 30k miles. It needs to be changed. It could maybe last another 10 years, but why risk it over a basic, inexpensive service? Like most things, time is not a friend to any oil. Would you put gas sitting in a gas can for 10 years in your lawnmower? I know I wouldn't. Change the fluid, boss.
Listen to S1C EM! Don't miss your window, do it now and you'll be fine. I bought a 2007 Grand Marquis with 60K miles and I cannot change the oil. Of course I could, but it would be risky and may start to causes slippage. I really wish the prior owners would have changed 4-5 years ago but they didnt and I cannot turn back time. Scotty Kilmer has made videos on this - watch them. If you dont change it in the window, then changing it causes problems. You're at the end of the window, so change it now!
What color is your fluid, Nico? You may not be too late. Age is the only terrible indicator on yours. If it's not burnt/brown I think you would be safe with doing a drain and fill at the very least.