yes, the rubber can seperate from the metal which is undetectable while its on the car. you can try to "test" it by slightly jacking up the engine (use a piece of wood on the jack to push on the oil pan). dont over do it, you dont want to go to far and actually break it when it wasnt broken

when you jack it up slighty, the car should want to go up with the jack, but if you shine a flashlight onto the mount, and you can see any space in between where the rubber meets the metal, then its toast.

the mount on the passenger side isnt difficult to remove, just difficult to "get to". its just 5 bolts, 2 on the front near a/c compressor, and 3 on the back down by where the transmission connector bracket is.

then you have the 2 bolts under the car and in the aluminum cradle.

you will have to jack up that side of the engine about 3" to remove the old part.