Towing ability of 2004 Suburban 5.3L, 4.10, 4WD

The summit is the hardest on vehicles. What makes it particularly daunting is that it is peaking around a curve plus there is nearly a blind rest area exit. It's not too bad during a clear day but on a foggy night (common there) it can be treacherous especially when people realize they need the rest area at the last minute.

Iirc the grades are 4-6%

Thanks

Jeremiah