Tow capacity rating

So I have 2006 4.0 double cab pre runner trd off road. It does not have factory towing package I put an aftermarket one on myself. I thought the pay load capacity on all the trd off roads was 6500 but if not with factory towing package option it's only 3500 is that only because it doesn't have towing package and tranny cooler since I added towing package would that bring up my max pay load? I just bought a rock wood pop up camper with toy hauler on front dry weight is 2800 so with my 4wheeler and gear it will probably be around 3800 my 4 wheeler is right at 600 lbs. I am installing 7 pin adapter with break controler will it be good? Thanks in advance

 

Yes I pull a hard side a frame pop up with a 4cyl. I think it's 3000lb.