1120kg is the load range on the sidewall.Pretty sure a 2500 Suburban requires a load range "E" tire. That's about a 3K lb rating per tire, max inflation 80 psi. Even a 1500 Suburban should be running XL tires which are a little over 2K lb per tire, max inflation 50 psi. That's why I'm saying the 44 psi max inflation on your sidewall is telling me the tires aren't chosen correctly for your truck.
There's some slightly conflicting information based on standards vs. how a particular manufacturer may have made a tire - it might exceed the standards, so the max inflation listed for a particular tire might be higher than what the standard calls for. Here's some more info though: https://www.tirerack.com/upgrade-garage/what-are-load-ranges-ply-ratings
What's the load range on your sidewall?
Richard
I'll dig deeper into this tomorrow - it's getting too dark here to read what's on the tyre - and reference it to the linked article. Remember I'm in the UK and possibly tyres here are marked differently than in USA. Tomorrow.