Any common 6.2L engine issues I should beware of? 2011 model

You need premium gas to avoid knocking

I would have the displacement-on-demand (DOD) 4 cylinder mode deactivated. They make full DOD-delete kits that also remove the mechanical parts but I don’t necessarily think it’s needed for all applications.

My 2010 Yukon Denali dropped a DOD lifter at about 98k miles. It requires removing the head to swap out the lifter and cost me about a grand. I got the DOD system electronically disabled and it no longer goes into the 4 cylinder mode. Really it’s a layer of complexity that the simple, reliable LS motor does not need. This is why you see more reliability out if a 98-01 5.3 than the newer LS motors.

I go into a bit more detail in this post:

LINK

Do they all have this DOD mode? I was not aware this truck had it. It is not a denali, just a Sierra z71, would that make a difference?

For that year truck, get the rough country leveling spacers. Very easy to install yourself.
1) Unbolt bottom two shock bolts on each side.
2) Use a prybar and push the shock up enough to slide the spacer in.
3) Reattach shock using the longer bolts that come with spacers.
4) Get an alignment.

With any lift, it puts a little more strain on the suspension because it is changing the geometry. With this small of a lift, the changes are minor.

Had these spacers on my 2010 for roughly 5 years and never had any suspension/drivetrain issues.