I have a 2006 Dodge 2500 5.9 4wd. I have a vibration coming from what I would assume is the drive train. I dont feel it at in town speeds but once I reach about 55 mph or above, I feel a consistent vibration while giving it throttle but once I let off, it goes away. I only feel it at speeds greater than 55 mph give or take. It is especially noticeable between 60-75 mph. I dropped the drove shaft and both rear ujoints seem good with no restrictions from movement and have no excessive play. I removed my front drive shaft and the vibration is still present. I do have play in my front driver side wheel (wheel bearing is going bad) but do not believe it is the culprit since the vibration is present only while on the throttle. The rear wheels have the slightest movement, maybe 1/16th of an inch or less unless I'm imagining things. Does anyone have some insight or could that front wheel bearing some how be the issue? Just doesn't make sense with the front driveshaft being out and nothing to put it under load. Any suggestions are greatly appreciated!