It's a 2wd and the rear diff plug, seems a little excessive to me. I noticed a deceleration noise (whine) over the past month or so but the dealer kept the truck 2 days and first said they herd it and it may be the pinion bearing and then suddenly the next day they can't hear any noise. Got back in the truck and heard it right after leaving the dealer. Did they change anything in the differential from 07 to now? Not sure but my 07 never had this much build up. Thank you for your responses and insight, a little frustrated now for sure.