Fill Trans Fluid or rebuild trans

Hi,
I had a similar problem and ended up having to rebuild. I changed the fluid first (which is a true chore) and after that the hesitation was still there, when I had the trans pressures checked the flares were in the low/reverse and the 2nd gear mostly with a small flare beginning in third. I recommend having it pressure checked to see what the problem really is. Some shops do that for free.
Hope this helps.