2002 Lexus ES300 with 197,000 miles. I admit that I haven't taken care of my transmission; it leaks a lot and 2nd and 5th gear no longer work. It has the code P0793 - intermediate shaft speed sensor "a" circuit no signal. That's the only code on the vehicle, using a Toyota dealership laptop scan tool (I work there as a tech). I plan to replace the whole transmission with a used one when I can. In the meantime it still runs and drives great for the condition it's in, but my motor shifts and clunks a lot when going in between reverse and drive. I replaced the dog bone engine mount on top as well as the mount on the bottom on the passenger side. I also replaced the transmission mount on the bottom on the drivers side. It definitely made a difference; the clunking/movement isn't as bad, but the motor still shifts and clunks a little bit, more than it should. I even made sure to torque everything down to specs. But I discovered there's another mount on the bottom in the middle that I haven't changed out or looked at yet. I can also hear the same clunks when going over bumps. I've replaced every suspension part on the front end a year ago except for the sway bar links, and the vehicle does sway a bit when braking or going over bumps. Maybe that could be what's clunking, but it shouldn't make the whole engine move and clunk from a dead stop just going in between gears. Maybe it could just be the transmission itself. I know the motor has a lot of life left in it; I always change the oil every 5k, it doesn't leak/burn oil/coolant, and has never misfired or anything like that. If the root problem is the transmission itself, it will get replaced like I said, but hopefully I can fix this problem before then with all the information listed.