Slight vibration when in gear, any help?

[cusco]

I recently purchased a 2006 Titan with 10,000 miles I have noticed that when I put the truck in drive there is a slight vibration you can feel through the floor on your feet and if you put your hand on the dash. It goes away in park or neutral. When driving it is there but goes away when you let off the accelerator. I was wondering if this was normal, if anyone else had noticed it or had any ideas what I should check? My 2003 ford felt similar when 4WD was engaged. The Titan is definately in 2WD as it has a totally differnet feel in 4WD. Thanks

[billwitte]

Remove from gear... Sorry, could not resist.