I would agree with Greybeard on this one.....
I do not think this individuals problems can get any worse by installing new fluid int he tranny. Unfortunately they have not specified the miles on this particular unit but one may assume it is a higher mileage unit.
I had similar problems with my vehicle and for $120.00 for a new filter and fluid versus $2800.00 plus for a rebuild, I chose to invest $120.00 first to resolve the issue and it worked excellent. My shudder went away and tranny no longer has any issues.
Besides the fact I took my vehicle into a reputable tranny shop only for them to say the fluid was fine. Well, let me tell you, when you look at the dip-stick, it looked and smelt fine, but with 90,000 miles and after dropping the pan, the filter was clogged and the fluid was BURNT. By looking at the stick does not give adequate results.
Do the regular maintenance and most issues can be resolved
I also ran LUCAS in there as well for an added boost of assurance.
GO WITH THE FLUID CHANGE FIRST and see what happens, what do you have to lose but $2680.00 on an unescessary rebuild at the moment?????