When I put it in sport mode, it doesn't seem to be as bad. It almost seems like it is downshifting in regular mode when you let off the gas and not doing it in sport mode but I could be totally wrong.

 

You are exactly right jalodge. I seems like the trans shifts down as I slow down, not enough to slow the Rover (as if I were downshifting to reduce speed) but as if the trans was following the Rovers speed and sometimes getting a little ahead of where it should be. I have driven cars with excessive back lash in the drive train and the SOUNDS like that but if it were that I would think it would do it all the time. I still think it is a vacuum issue or a vacuum valve that controls the trans. Thanks for everyone's help and I will try all of your suggestions before I take it in and let them guess at it.

 

clunk is the sum of the backlash in all the drivetrain components

 

Let me know what you come up with. Mine also seems like the transmission does not shift when it should. My cruise control doesn't work but the light comes on so I wonder if that has something to do with the vacuum system.

 

Let us know if you ever catch this "Wild Turkey." I'd like to know if there is something I can do about mine.

 

For those of you who are still following this thread, I think I may have found the problem. I was getting multiple misfire codes also but thought it was unrelated to the clunk. My mechanic said it sounded like the misfires were being caused by a vacuum leak which is what I had always thought the source of the clunk was (trans getting wrong messages). I searched and could not find any vacuum leaks so I took the Rover to him. He performed what he called a "baptism" by taking a jug of water and pouring it over the engine while it was idling. The idle smoothed out and he said I had bad injector seals. He replaced the injector seals and the clunk is almost completely gone and much much less savior when it does happen. I would have to day that now the Rover is normal and I am probably "over listening" for the clunk.