Hello,
I have a 99 RX300 with 125000KM. I've had EXACTLY the same symptoms as you've described, only its very infrequent - but perhaps more pronounced. Four times over the last year, I start the engine, coast down the hill, and when I accelerate at the bottom, my tranny hesitates/clunks/grinds. It becomes "normal" once I reach operating temperature. On the second incident, I took it to the dealership, but they were unable to reproduce the problem. On the third incident, I left the truck overnight with the dealership, but again, they could not reproduce. (As I've said, its happened only the four times, so I can understand the dillema...on the fourth time, I didn't bother.)
I live on a long hill, a few hundred yards/meters up. I've had it happen in both the summer and the winter. On two of the occasions, I had started the car and left it idling for several minutes, not long enough for the temp needle to go a past halfway though. (In both cases, the clunking was VERY harsh.)
I've had the truck since new, 100% dealer serviced. They've did a drain and fill on the tranny fluids every 24000KM. Tranny fluid always has and still looks fine.
If anyone can suggest a course of action or provide any information, it would be greatly appreciated.
