I’ve noticed this during extremely cold temperatures i’d shift it from P > to D Delay I can can feel the car going into gear a few seconds later the weather has been warming up & now it doesn’t do it or is on and off with it. should i change the fluid regardless?

 

A drain and fill wouldn't hurt with another one or two before next winter. It's hard to say without knowing year, mileage, trans service history, etc. I'm not a mechanic but when chasing down transmission problems, the condition of the fluid usually comes up. Best to be able to cross it off the list of potential problems. Best of luck to you.

 

And make sure your fluid level is not too high or too low. If you do a drain and fill and the fluid smells bad or is very dark, do at least 3 drain and fills.