Can anyone tell me why my truck has a very noticeable vibration while accelerating in 4x4?
I can feel it in the floorboard right above the front differential. I have always noticed a slight hum/tiny vibration when at 50-60 mph but never this bad before. Its definitely a new vibration.

Is this a sign of anything going in the front differential?
Would a 4x4 launch on dry pavement mess something up? I've launched in 4x4 2 times. As far as power I only have the Juice and lp, so no more then most.
Could the front driveshaft be out of balance or need grease? :(

u-joints could be bad or seized.
get under truck and see if you can move driveshaft up/down or take it out and move u-joint around and make sure it moves freely.

Thanks dirtyedge, I'll check it out. I did do a quick visual of the front shaft and it is quite rusty and the u-joints don't look any better.
So its probably not anything in the case then? :cool2: