Another thing to consider on these test drives: I live in Los Angeles and we have some really bad freeways. Concrete base and they get cupped out from all the truck traffic. I can run my new High Country down these and it will get bucking so bad I can't even make a hands free cell phone call. Most of you would swear there is something bad wrong with the pickup as the vibration is absolutely rhythmic as it is in a defective vehicle. Yet I can run this same truck on new pavement from 0 to 100 and it's absolute perfection. If you are not familiar with the firm ride of these new truck pay attention to what you are running on for the test.
I have a 2016 5.3 and I added a 1/2 quart to bring it to full at 4300 miles but in fairness I didn't check it at delivery to see if it was actually on the full mark. I just run it as original.
I guess this is why Chevy will send the customer satisfaction survey in the first 30 days, before reality sets in and the new owners are more aware of their problems. I had like 500 miles on mine when I got the survey. I gave the truck high marks. Actually I like the truck just disappointed in the tranny.