Yeah its not listed in the owners manual and the dealer says "bring it in and we will tell you when based on color/smell and performance." They say around 30K miles but that seems early for newer cars.
IIRC, the manual for my '06(also an A-W 6 speed) called for 100k. Don't quote me on that, though.
However after looking at some UOA's of T-IV(same as Mobil 3309) I came to believe that it isn't a long life fluid.
So, I did two drain and fills, first at 50k, then the next one about 750 miles later. The fluid should be good and refreshed now till 100k.
I'm not sure if they're exactly the same trans. But your manual shold state the spec of fluid, and since you're already looking at 3309(which I found impossible to locate through normal retailers) I'm assuming it specs T-IV.
If so, there's used UOA's, and maybe even a VOA, that may make up your mind on fluid change intervals regardless of what dealer or manual says, just search.
If it's T-IV, I'd start thinking about freshening up that fluid pretty soon.
30k is about the limit for ANY ATF. 50k is if vehicle is very gently driven. To go longer, you need inline filtration, sometimes additional cooling, and a UOA to prove that the ATF is suitable for continued usage.
Any of the universal or multi-vehicle ATFs that mention 3309/TIV can be used. Plenty of good choices.
The owners manual states JWS 3309 in the trans with no change interval recommendations. Do I need to drop the pan to do this like the olden days or is that just a waste of time because I do not have a flusher.
There is NO pan to drop. 3309 is the same as T-IV and I buy it at Toyota for ~ $5.xx per quart. The Mazda CX7 uses the same 6spd AT and I did a plug drain & refill at ~ 30,000 but, the fluid looked new. Refill was ~ 3.75 quarts. I think a 50K plug drain and refill is more than adequate unless you are really abusing it.