domenics

Thanks for the replies. Most of the time there is the noticible thump as you indicated. The intensity seems to vary quite a bit. I notice it mostly when I am backing out of my garage in the morning. This is when the 'thump' is somewhat audible. I did have one of the specialists at my Lexus dealer test drive it today. He indicated that it is normal. I guess I'll have to live with it and try to get used to it.

I have had my RX400h for about a month now and enjoy it very much. I do have one issue that that I'd like to know if other drivers are experiencing. During acceleration from a stop or very slow speed, there is a distinct clunking noise when the V6 engine starts automatically. It's very noticible and somewhat annoying. It feels like the V6 engine is engaging with the transmision. Is this normal? Thanks very much!