Bad vibrations

by shimmy I am assuming you mean side to side? and is the whole truck doing it, or just the front end, or the rear, or are you only feeling it in the steering wheel? go to a tire shop and get your tires checked.  could be a bent rim, tire balance, broken bead in a tire.. its cheep to eliminate any issue with the tires first

Well, steering alignment is basically never the cause or cure of vibrations. So there’s that. 
however you asked a horribly vague question, so don’t expect to get any real answers. 
save for morsnow talking about a condition that is/has been reported in some GMs and some Rams. But not widespread. 
good luck. 

Chevrolet/GMC has had this issue for many years, it is due to the solid frames they use.  Many notice the passenger seat shaking while driving alone.  In the late 2000's they recommended new body cab mounts that were softer, then in the later 2010's tire balancing was crucial.   Most found that having your tires Road Force Balanced was the key to fixing the issue versus normal spin balance machines. Road force balancing places pressure on the tire (like a road surface) and better recreates what many are feeling when tires are balanced as well.  Most GM dealers have Road Force machines in their service bays because of this, but many never go to their dealer for tire service. 

Rear tire out of balance?