Actually, yzerman, GM does recommend Dexos for your 2011 truck, even if it's not printed on the cap. BUT... it's your truck. If you aren't concerned about any potential warranty issues and don't use the Oil Life Monitor (OLM), SuperTech will be fine.
Maybe you could compromise and use Super Tech Synthetic 5W30 (even though it isn't Dexos certified... yet). That would at least bring the OLM back to spec... assuming your truck has a OLM.
HOWEVER... at my local Walmart, Quaker State Ultimate Durability was a buck cheaper for the 5 gt jug than Super Tech Syn. I know what I'd buy.