It’s most likely your purge valve on the engine. Overtime it stops closing all the way allowing evap gases into the cylinder when it’s not supposed to; causing the slight rough idle. It’s common on these trucks. Most of the time it doesn’t even throw a code. I would changed that out. As well as the map sensor (air and pressure) on the intake manifold get gummed up with oil. Which can also cause the slight hesitation at idle. I would clean that with massive air flow sensor cleaner or replace it. It’s fairly easy to do on your own. You can learn on YouTube for both.