I bought my T100 a few months ago and Changed the oil, oil filter, the oil in the transfer case, front differential, and rear differential. Within a week or so I started noticing the truck would vibrate, only when the truck is not moving, and only if the truck is in Drive or Reverse. It does not vibrate in Neutral (sounds like its under the hood), I know when the truck is in Drive or Reverse it Idles lower at a stop than when the truck is in neutral and that is when i hear/feel it. I checked the oil level today and it looked fine.

Any Ideas?