i'm well past the "should i" stage so i thought i would share the experience so far.
dropped my '08 4.8 at my indy's shop today. flush all diffs and change trans fluid. 76k miles. i asked for the trans filter to be changed also.
so he calls me about 4 and asks "are you sitting down". turns out the
transmission filter and pan are one piece of plastic.

his cost $300. but at least that includes the gasket. we are both simply amazed and not in the least amused by this. add in the fluid at $40 a liter and i might need to rob a bank to change out my trans fluid.
more to come as it unfolds.
if i don't laugh about this i might just be driven to tears..............