The 6.2 engine has 420 hp/460 torque so no problems pulling in Rockies or high head wind flat lands on all day runs.
If your 2018 has the NHT tow package this gives the 1500 GM truck a 4300 rawr and good for around 1800-1900 lb payloads.
My wifes std duty '16 1500 chevy crew cab 4wd 5.3 6 speed.... rear axle weighs 2360 lbs. Your '18 rear axle will be close to that number unless you carry the kitchen sink. :).