1999 323i

[Fred D]

I have a problem with my car. When I begin to drive my car when I get to about 20mph there is a thumping sound and feel that comes from the area under the center console. This issue was happening about 1 month ago. I discovered that one of my transmission mounts was completely broken. I replaced the transmission mount and the drive shaft center bearing. It seemed to have fixed the problem to a point. After those part were replaced you would still feel the thumping if you would stomp on the gas for a quick take off. Just two days ago it has gotten worse. It is now acting the way it did before I replaced the parts. What should I do? I went ahead and replaced both of the transmission mounts last night and that did not fix the problem. The center bearing did not look broken what else should I replace or check?

[supervisor1886]

if the mounts are fine check the engine mounts. Other than that if you feel the vibration at any speeds you might have a damaged driveshaft or yokes, bearings, etc.

The other thing to suspect is the shifter assembley. Maybe need to be adjusted or the bushings were damaged (if you have a 5spd).

Since you replaced it the tranny may sit somewhat different. (check for any aligment issues), i recomend to go to a shop and lift the car up and see if any exhaust or whatever parts might come in contact when theres torque on the tranny.