You are very close to or a bit over capacity with a 4700# load. I will explain below. However, you HAVE the 4 Runner, so I would give it a try before upgrading. The truck will not disintegrate if you are 50# overweight, but you may not like how it handles.
The 4700# tow rating assumes a load of bricks on a flatbed trailer. It allows for one 150 lb driver (2014 0r older) or 2 150 lb passengers (2015 and newer), NO other cargo in the 4Runner, and a full fuel tank. For American models, it must be reduced by the weight of all optional equipment above the bare bones base model. Toyota may be better at real values. Remember the drag from that huge frontal area as well.
Good Luck!