i had an 86 trooper. It would have this winding/scraping type noise comming from the front(possible related to the 4 wheel drive) which would occur when in 2 wheel drive especially during cold mornings after the truck sat overnight, while coasting.

Then when it did stop, it would stop when I stopped the vehicle, in doing so, it made a slam sound like something loose fell into place then the truck would be fine until it sat for a few hours

Anyone have any ideas, is this a common problem.

I had the same noise and it went away when I switched my auto hubs to manual ones. Something to do with the hubs trying to engage.
Hope this helps ya,
Nick

I had the same proble exactly!!!(drove me crazy) on my 87. it was the auto-locking hubs. the same type hubs are still used up to 93 for sure maybe later. no problem w/ my 91. I think they changed the frt. diff. in 88 which may have solved the problem. warn makes a good manual hub for just over $100. a set. thats whats still on my 87.