RE: Car shaking periodically
 

Ok, I finally got this fixed!

Went to a service center for another problem and asked them to take a quick look while they were there. They ended up replaceing the transmition fluid because "it didn't smell right". I was pretty skeptical, but it has not happened once since! Plus, the car accelerates a LOT smoother now, before it was pretty jumpy. The check and replacement cost almost $200, quite a bit, but they run a good operation there so I decided not to go looking around.