9. Having as quiet a cabin as possible was a key area the engineers spent extra hours working on. Chuck Lemont, Vehicle Development Engineer on Vehicle Acoustics gave us the inside scoop on the 2014 Sierra's cabin. “The most noticeable item to the customer is that the doors are inlaid to the body. The reason we did that is it allowed us to use triple seals, which result in much better wind noise performance, a much quieter cabin, with much less wind noise and also a more repeatable design where it's easier to build the vehicle the same every time."