So, I can speak from experience on this one and will try to put as much detail as I can:
Had a 2014 Silverado LT Z71 1500 Crew Cab, nice truck no issues. Swapped the dealer 18's for XD Wheels 20''. Put 305 55 20 LT Cooper Discoverer AT3 tires on the wheels. They added 59 pounds each to the vehicle and the suspension was stiff, but still after leveling the front end up 2'' there were no issues.
Now, this is where you need to understand.
Traded the 14 in just recently and got a 2018 Silverado LTZ Z71 Crew Cab Redline Edition. Very nice truck with more upgrades. Same suspension though as the shocks, leaf spring and ride is the same for Z71's. Truck came with 20'' Redline edition wheels, so I kept them, but the truck came with Goodyear SRA junk tires. Sold those as take offs. Here is the kicker, had the opportunity to put the 305 55 20 tires from the 14 on the 18, but I elected to keep the stock size 275 65 20 and put on Cooper Discoverer AT3. Best damn decision that I made. Not only is the ride like a Cadillac compared to the 14, but I can definitely tell a difference... (Don't use LT tires if you don't have to) And if that doesn't sell you, just drove 4 hours to Williamsburg, Virginia, beautiful drive by the way minus DC traffic, but the ride was smooth and did not feel as though you were running into a curb when you hit a pot hole. Also with the 275 65 20, as they were the stock size, I didn't have to spend $400.00 to level the front end.
Hope this helps in your decisions.