A couple people of asked about the e-lockers but I have never seen a response to see if that maybe the issue.
I recently leveled my truck and now I notice the vibration problem between 45-48 mph. I have bigger tires as well. I usually can let off the gas for a few seconds and let it roll and get back on the gas and most of the time the vibration stops. Mine is not really bad but noticeable, so far I can live with it. Not sure where the problem is at, hopefully someone figures it out.