I'm just finding this site, but I have the exact problem you're describing. I have a 2004 LC, my third LC, the others, a '00 & '02, were destroyed by hail storms and I had zero mechanical issues with them. I bought the 04 with 117k miles, I didn't notice the shudder for a few months, probably because I'm a heavy accelerator. Mine currently has 175k miles, this is the only issue I have with it. During soft acceleration the shudder hits right at 32mph. It was occasional, but then more frequent. It started happening every day when I was taking my son to school since I have to drive up a hill in our neighborhood, which is ideal conditions to recreate the shudder. I went to the dealership, they couldn't recreate the problem. I went to a transmission specialty shop, described when it happens, they got it to so it repeatedly. They found the bulliten from Toyota and said the only option is replacement. $6000 for a Toyota tranny, $4800 for a rebuilt. I wanted to vomit lol. I haven't tried a flush, I've heard mixed information about transmission flushes. The tech at the transmission shop said this issue isn't necessarily fatal to the transmission. The gears aren't slipping, it's just the shudder. It feels worse than it is because the whole car shakes so violently. He suggested if I can live with the shudder, just continue to drive it bc fixing is so expensive and if it eventually fails, then replace it, but otherwise it should continue to drive just fine. I noticed talk of a synthetic flush, I'm nervous to do that but since the last comments are so old here, I'm wondering if any of you have tried this and had any luck with the flush? Thanks!