My bro has a 2002 GMC Sonoma ZR2 4.3L 4x4 e cab pu and he tows a pop up camper and the pu box loaded with gear. He says it pulls that OK.
He was telling last fall they stayed at a campground with his son and family. Son has a 26 ft travel trailer they tow with a 2007 Silverado CC. Anyway there is not much parking area at the lot so he would park his Sonoma at the tongue of the trailer while the rest would park in a over flow lot. People driving thru the campground would stop and look at his little Sonoma parked there and not seeing another vehicle assumed he was towing the big travel trailer. Most would just shake their heads and drive on, a few could not resist and would ask him if he was really towing the big trailer with the little S15 GMC. They got a lot of laughs from that.