My van is experiencing some rough vibrations, especially at low rpms, seems to smooth out once driving. I suspected motor mounts, so I replaced the front motor mount which was failed, but I still have the same symptoms. The side motor mounts seem fine and I can't find the rear motor mount.... any suggestions?

3.3 L with 180k miles.

thanks!

 

Welcome to DF
Your van as you know has 4 motor mounts. 1st one on the front of the motor, 2nd back of the transmission, 3rd center of the engine and trans on the front bumper side and the 4th is bolted to the transmission case near the crank sensor. Most likely you either have a bad axle shaft or tire. Try rotating the tires first and see what happens.

 

thanks for the welcome. Sorry, forgot to mention that the vibration occurs while parked. I guess I need to get the van jacked up high enough to where I can really get to the back side underneath and find that 4th motor mount. Does anyone have any diagrams/pictures of where that is located and how hard it might be to change?

thanks!

 

Had same problem, vibration while in drive gear and stopped. Rear (transmission) mount was the problem. Want to verify? have someone with emergency brake fully engaged and the foot brake applied shift to drive , engine running, then put a hydraulic jack under the differential portion of the transmission (rear of the transmission, Directly under the mount), As soon as you start unloading the weight of the engine at that rear mount with the jack, the vibration goes away.