Hi all
ive seen that on other cars sometimes when there is a shudder you should change the fluid out twice because it doesn’t actually drain fully.

The transmission is otherwise fine (shifts smoothly) but the car sat for a while so I’m thinking the fluid is just bad. I’ve changed it once 1500 miles ago (just drain and fill, no power flush or anything - had it done by dealership). shudder is still there between 1 and 2

should I do it again? Is there a filter or something I can try to mess with?

any other ideas? What about those additives? This car says dexron II or equivalent and I’m afraid to put new products in and eff it up.

car has 103k on it.

thanks!