There are a lot more people with issues than the ones posting in this thread, most people will try to get it fixed a couple times and then just give up. After enough BS from GM they eventually just trade it in. Thats why I see tons of used 14, 15, and now 16 GM trucks on used car lots with less then 10,000 miles on them and thats a DAMN shame. Its not just vibrations that GM doesn't want to fix, its just about everytime you bring your truck to the dealership that they will usually call it "normal" or "could not duplicate". Its just a matter of time before quality issues catch up with GM and start hurting their profits, but unfortunately for customers right now they're sitting fat and happy and don't give a shit!