My dad's '83SD has been making a "clonk" sound when you start it up recently, it used to be a very small sound, but now it sounds and feels like the tranny is slamming against the sidewall of the tunnel when it starts up, the sound is a muffled "poom!" emitting right from the driver side of the tranny tunnel and it only happens when starting the car, which always works fine. Is this a symptom of a worn out tranny mount? Or something of the like....his motor mounts are practically brand new, the engine sits in there like a rock compared to mine, which roams the engine compartment at will..... So I was just wondering what this could be, its starting to get annoying.....

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