This is the driver side motor mount I found on my 99 XJ. I have had this car all my life and don't think that anyone has ever been in here. But I have never seen anything like this described.

I know when the mount gets worn the XJ engine can slide forward and the fan can contact things. It seems like the rubber shim that has been inserted there would prevent that from ever being an issue so I can see its utility.

Someone sugested it was probably just worn and that was a bad fix to kick the motor mount down the road. But the motor mount isn't worn at all, rubber looks great, there's hardly any top Gap. And that shim is specifically designed to go in there. It's not a flat piece of rubber. It's designed to fit and it has a cavity molded into it to accept the Bulge in the motor mount where the bolt goes through.

Then the other odd thing is nobody's ever worked on the motor mounts on this car, or done any major engine repairs for that matter.

In the first years of its life the dealer was servicing it and so it's possible the dealer could have done something without my knowledge. Maybe there was a TSB about the engine sliding forward and so this was their solution? It's a mystery to me.

Whatever it is it looks like it was done well and deliberately.

Has anyone ever seen this before?

 

Upon closer inspection the big rubber shim appears to have a Chrysler logo and part number on the inside of it so I don't think it's a ham-fisted solution. I just don't see anything about this in any of the parts manuals or mentioned anywhere else on the internet. Anyone have any idea?