Body Guys - help Please !

[Leinie]

I have a strange issue with my 99 Suburban. Just normal driving on city paved streets every little bump makes the doors rattle like they are about to come off the hinges. I've tried to shake them when open and it doesn't seem as if the hinge pin bushings are bad, The hinges don't move, they are all welded.
You know how it is when your door isn't closed all the way ? Or when your driving on a gravel road and hit a patch of bad washboard- That's what it sounds like , but they are all closed tight. Almost like the latch doesn't lock on the pin tight enough. Are the latches adjustable ?
It's enough to drive me crazy- the thing barely has 50,000 miles on it. ( yes I said 50000)
The 98 I had before had 3 times the miles and was tight as a drum, Did they change something in 99 ? Doubtful but I know GM will do anything to save a buck.

The doors seal air out very well, there is no wind noise, just that damn clunking , rattle. I dare not take it on a gravel road - I appreciate any suggestions, or other help you can offer.