try this to test if you need new trans or motor mounts,place a floor jack under the engine oil pan with a piece of wood between the jack and pan. gently lift the engine till the strain is off of the mounts. if the vibration stops, you need new mounts. replace them one at a time till you have corrected the problem. start with the one between the engine and the radiator. this one has the most strain. hope this helps.
