That is exactly right. If you are in 2HI, you can run on a 2wd dyno, period. That sticker is probably a CYA (cover your a$$) type sticker so someone doesn't screw up and have it in A4WD and have the truck take off on them.

 

ohh yeah forgot about thooosssee stickers, you should read some of the warings that came with my envy phone downright stuipd

 

go to a gm dealer and have them run a vin check, they can tell you everything you need to know about your truck