Clearly if this started right after the mount was replaced then we have to suspect it was a faulty mount. This happens when the mount is grounded which is basically the rubber is not insulating the engine pulses from the frame. If this is metal to metal or just a faulty mount it will transfer the pulses to the frame and you will feel it.
Here are some guides that help with this:
Again, if this was after the replacement then I would have it inspected again because either that mount was not installed correctly, was a faulty mount, or you have another mount that failed.
Let me know if you have questions. Thanks
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Monday, March 1st, 2021 AT 4:47 PM