Not to revive an old thread, but for anyone looking in the future for what he remedy was, it was just the dealer adding the lubricant others have mentioned.
Anyone know if this lubricant should be added to the front diff as well? I've spent most of the time driving in 2WD since August, but have engaged the 4WD more with the rain and all the wet leaves around these days.
Also, has anyone has a bit of a burning smell come from under the truck, about where the front door opens and you would exit the vehicle? It doesn't smell at all like a burning liquid(not oil, antifreeze, etc.), or burning debris(leaves). Also not exhaust related. Just hot metallish stink. When I approach the hill to where I live, it's got a bit of an elevation change, maybe 200-250 feet, and it isn't too crazy or intense, just there. Seems like it should be taken in stride. I haven't noticed it the whole time I've had the truck, and believe me, after towing back through the mountains on a 110+F day back towards the end of August, any 'new truck burning in smells' should be long gone. Thoughts?