Hey everyone… I have a 2021 Suburban RST and I noticed it has a knob for selecting 2W or 4 
or 4 
. My last vehicle just had a button for AWD, so I’m a bit confused. The weather’s pretty nasty today, and I want to know what setting to use for driving in snow and slush. Can someone explain this like I’m 5? Appreciate any help!
Page 236 of your owner’s manual has the details: Link
For snow and slush, use 4HI for normal speed driving. 4Lo is for when you’re really stuck. If your truck has an auto function, that’s usually the best option—it only engages when needed. I live in MN and use auto when it’s snowing and rarely need 4HI.
I’ve heard that auto 4WD can be risky for your transfer case if used all the time.
That’s true. If you leave it in auto all the time, it can cause issues. I’m usually in 2HI and only switch to auto when the roads are slick. I turn it off as soon as conditions improve.