Will replacing transmission mount solve the noise problem?

This is about my 2000 Nissan Altima, Automatic Trans, FWD, 102300 miles.



My car has a scary knocking noise when I accelerate from idle, and when I brake at very slow speed. I brought it into a dealer, they said the idler pulley bearing is bad and two cross member motor mounts split open.



I let them change the pulley bearing ($111 ). Then, I brought my car to another mechanic who changed the 2 motor mounts for me ($310). --- the dealer would do it for $528.



BUT, the noise is still there! The last mechanic guy told me that my transmission mount is very soft but no crack yet. He can change it for $200.



My question is

1) How could I know if changing transmission mount will fix my noise problem?



2) What harm can a soft transmission mount do to the car other than making noise?



3) Is the price the mechanic gave me sound right?





Thanks!Will replacing transmission mount solve the noise problem?
A Soft Transmission Mount can Cause Noise a shortly Break completely, Yeah Replace it. Sounds a little like the mount isn't the complete problem, sound like your brake Pads or Shoes may be Hanging Up and need to be Inspected and/or repaired.



To Check the Mounts; With the Car %26quot;Out of Gear%26quot; Reeve the Engine Not Fully but Quickly 2 or 3 times, Now %26quot;In Gear%26quot; 1 or 2 times. Feel it In Gear?Will replacing transmission mount solve the noise problem?
Loud noises are pretty easy. I'm surprised these guys couldn't fix it. I think the transmission mount will be pretty easy to replace, but I don't know what it costs. Go to rockauto.com and look up a transmission mount for your car.



However, I'm not convinced it's a transmission mount. The fact that it makes the noise under low-speed braking is not really consistent with the noise being caused by the drivetrain.