Hi,
I have been following your post regarding the rough idle when you have your truck in Drive and are stopped. My truck has been having the exact same problem, but I think I may have found the solution. Recently the idle got really bad...whether in D, P, or N. I tried everything you did. I finally resorted to taking it to a mechanic last week who discovered that the bearing in my fan clutch had given out. The seal had broke loose and one of the balls came out as well. This is what was causing it to run so rough recently. The mechanic told me that it appeared that the bearing had been wearing over time and could very well have been the culprit causing the rough idle while in D and stopped. I had to order a new fan clutch and am supposed to receive it this coming Wednesday. After I get it installed, I will let you know if that solves the problem with the rough idle while in D and stopped. Don't give up yet!