I just had the dealer do the fluid flush and fill per the TSB. They didn't give me any guff about it either. So far, I am not convinced the fluid flush did anything. I am still getting the same feeling at around 1500 rpm between 45-55 mph. I have only driven about 125 miles since the flush, they said give it at least 200 miles for the trans computer to recalibrate. But if I don't notice a change after 200 miles, it's gonna go back for a further diagnosis.If you take it to an independent shop, keep one thing in mind, they do not have A dedicated flush machine for any one particular manufacturer, such as GM, so there flush machine is contaminated with all manufacturers fluids. I have seen YouTube videos that talked about this. Be careful with independent shops especially on complete transmission flushes. Flushes are not good, but in your case, that is the only possible solution.