Possible Transmission Problem?

[dknight211]

Hello everyone, I have a 1992 LS400 with 140,000 miles on it. Its has the usual common problems for the 90-92 series: dark clock, cracked leather seat, etc; nothing major. I'm the second owner of the car. I bought it about 10 years ago for 120,000 for $20,000. It's been a great car with no major problems, just basic maintenance.

However, recently, I've noticed a strange problem. When I am accelerating from a stop, you can feel the car make a "thump". Its hard to describe in words, but it feels as if the pick-up is not smooth. The strange part is that it happens even when the car is not moving. If I'm stopped at a red light or the car is idling, it randomly makes a thump.

I've checked the transmission fluid and nothing seems to be wrong.

Another interesting thing I've noticed is that my car no longer drips water after the air conditioning is turned on. In the past, it has always dripped a lot of water after the AC has been running for a while. However, recently for the past couple of months, no water has dripped at all. I've read a lot about other car brands that have the condensation drains clogged and the water eventually starts draining into the foot area.

If anyone has had this problem or knows of a solution to any of these problems, please let me know?! THANK YOU! =)

[SRK]

The thump may be nothing more than a torn transmission mount. It does sound like a driveline problem, like something is shifting around a bit. Not a big deal.

The lack of AC water may be from a low system charge. Is the AC as cool as it was? If not, then the evaporator core is not getting cold enough to cause condensation. Have a good AC shop check it.