Iíve forgotten mine several times towing, the last time I had went about 50 miles, and noticed when I pulled in a McDonnalds for lunch, when turning the front tires was digging into the freshly laid asphalt.
After that I wired in a small amber led light that illuminates only when Iím in 4 wheel drive low and high.
That little light on the knob, is pretty much useless unless itís dark and hard to see unless your looking down.
Your not the first and wonít be the last, as mentioned above you should be ok.
2007.5 GMC "Black" Sierra SLT 3500HD SRW C.C. 4X4 LMM Z71
DIY stock airbox mod, aFe ProGuard 7, OEM drop-in
EFILive ECM ATP - Heavy Tow Tune with Turbo Brake
EFILive TCM Duramax Tuner
DHD Cold Side High Flow Intake Pipe, DHD PCV Re-route, AirDog 4G100
Castrol Hypuron/Vecton 15W40 synthetic blend oil
Donaldson P550832 2 qt oil filter
2007 GMC Yukon Denali "BLACK" 6.2 gasser, DIY stock airbox mod, K & N OEM drop-in, Airaid intake tube, EFILive TCM tuned