2016 GMC Sierra 3500 SRW vs. Ambition 38FB - Am I safe?

Hi All, I am pulling the trigger on an Ambition 38FB this week. Here are the specs: - 9,000 lb. axles - GVWR is 21,460** - Dry weight: 16,000 - Pin weight is 3,710 **I'm told the GVWR is so...